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

quozl

Cheers Doozerie. I've heard those arguments before though and made my best judgement on it based on the weight of the collected studies I've read. I completely agree that it's not clear cut.

doozerie

quozl wrote: »

Cheers Doozerie. I've heard those arguments before though and made my best judgement on it based on the weight of the collected studies I've read. I completely agree that it's not clear cut.

I'm not disagreeing with your view, by the way, our views seem to be very similar in fact. The only reason that I quoted that one line from your post is that I think it's a good example of how we can unwittingly leave logic out of what seems on the face of it to be quite a logical conclusion/view. That's not a criticism incidentally, just an observation, I do it as much as anyone else.

I think we all do it across the board actually. A common example of it is casually assuming that travelling by plane is extremely dangerous compared to travelling by car, a view that seems fuelled more by emotion than fact. A closer to home view being that commuting by bicycle is far more dangerous than by car.

Basically, I think our assessment of risk is rubbish, all too often - amongst the most militant of those who call for obligatory helmet wearing, I reckon quite a few of them would walk down a stairs without holding onto a handrail (leading to certain death, according to some), don't check the state of the brakes on their bicycle regularly, might drive "just down the road" in their car without putting on their seatbelt, might let their young kids play unsupervised out on a road with passing traffic (depressingly common where I'm living), don't wash their hands properly between handling uncooked and cooked meats, etc. It's pointless challenging the entrenched view of such people if they adopt the position that helmets are essential, I think the only hope of having a reasonable discussion about the topic with them is to challenge the logic by which they reach that view. That's what marks this thread out as being useful actually, the fact that it involves mostly the latter.

quozl

doozerie wrote: »

I'm not disagreeing with your view, by the way, our views seem to be very similar in fact. The only reason that I quoted that one line from your post is that I think it's a good example of how we can unwittingly leave logic out of what seems on the face of it to be quite a logical conclusion/view. That's not a criticism incidentally, just an observation, I do it as much as anyone else.

Cheers Doozerie, I got that but you made false assumption about me there so I felt the need to reply.

I've actually put a whole lot of logic & thought into my position on this but I wanted to express it glibly rather than put yet another page of writing down on it!

For example speed has been repeatedly found in studies of helmet use to be a major contributor to injury rate.
I don't believe that time spent in the air is a significant effector of damage on impact as you will slow very little from air resistance in the fraction of a second it takes you to impact. I do believe the angle you impact at will make a difference as like you said, if you slide the force is absorbed over a longer period of time which will cause less injury. I don't believe helmets impact on that unless the helmet catches on something or its increased size results in you clipping something solid that you would otherwise have missed. Both of those are possibile and have been slightly explored in studies.

In my opnion there is little evidence for helmets causing increased injuries. There is little evidence for helmets causing decreased injuries. This study would be the strongest evidence that I've seen yet for either side. Note, strongest not strong

I've a MSc in medical science which by its nature included analysis of studies like this as well as exploration of the personal view of risk and how innately bad people are at it that you describe.

Which is all a bit long-winded and I hope you can see why I wanted to put it glibly instead! The above is still only the mildly less condensed version.

I still stand by - based on my own best attempts to use logic and reasoning after reading a moderate amount of the literature - my claim that I'd rather crash at 15kph without a helmet than at 40 with one

You can of course argue with my conclusions but please don't suggest that I reached them without an evidence based logical approach. I hope you can understand why I'd find your suggestion with me as the example a bit insulting - unintentially of course - and feel the need to reply.

magicbastarder

doozerie wrote: »

Those are just anecdotes, they obviously prove nothing.

in a sense though, anecdotes are the basis for proper data - which is made up of multiple datum points.

i saw mention above that there would be no poll on helmets, which i found puzzling; it's not scientific, but given there's a lot of interested cyclists on this forum, it's be interesting to learn if (for example, i'm not trying to pre-empt a possible result) on the whole the reaction would be 'i believe that a helmet has saved me from more serious injury than i actually did suffer'.

tomasrojo

magicbastarder wrote: »

in a sense though, anecdotes are the basis for proper data - which is made up of multiple datum points.

No, that's the problem: an anecdote is a memorable story. Data is systematically collected observations, both mundane and extraordinary, collected by someone who doesn't distinguish, or preferably is unable to distinguish (blind studies).

A collection of anecdotes about helmets would be mostly about things that don't happen very often.

RayCun

To draw an analogy with seatbelts (not that I'm suggesting helmets are as effective as seatbelts), if you polled drivers on seatbelt use, you could get

95% a seat belt has never saved me from serious injury
3% I think my seatbelt lessened my injuries in a crash
1% I was in a crash with no seatbelt and I was grand
1% I was in a crash with no seatbelt and I had a serious injury

which isn't very useful data

doozerie

quozl wrote: »

I still stand by - based on my own best attempts to use logic and reasoning after reading a moderate amount of the literature - my claim that I'd rather crash at 15kph without a helmet than at 40 with one

You can of course argue with my conclusions but please don't suggest that I reached them without an evidence based logical approach. I hope you can understand why I'd find your suggestion with me as the example a bit insulting - unintentially of course - and feel the need to reply.

My apologies, it wasn't my intention to seem to be arguing with your conclusions. You'd even stated that your summary was a little facetious, and I got that you weren't declaring it as fact, what I wanted to raise was the idea that many people would reach that conclusion without putting any critical thought into it at all, much like many people (me included) do about other topics.

In short, I couldn't argue with your preference to be wearing a helmet in a crash at 40kph even if I wanted to, and I wasn't trying to. As far as I am concerned I couldn't support such an argument with anything substantial. Based on my experiences I reckon that I'd probably fare better in a low-speed crash if I was wearing a helmet but with nothing but anecdotes to support that view I wouldn't expect others to be convinced to share it.

So we have two different views, which might be construed as opposing views, but they really aren't as far as I am concerned. We both just see potential benefits of a helmet in different circumstances and I see nothing contradictory in that at all. I don't think there is a right and a wrong view when it comes to the potential benefits of helmets (apart perhaps from the stark views at either extreme end of the scale, which don't seem to take evidence and reason into account), much like there is no right and wrong answer to the question of what is the "best" colour (it's blue, obviously, except on Saturdays when it's orange, and Wednesdays when its red, ... ).

smacl

quozl wrote: »

For example speed has been repeatedly found in studies of helmet use to be a major contributor to injury rate.

Roughly, I would assume the initial force of impact will be determined by speed at which the head (or other body part) hits the ground divided by the sine of the angle of incidence, the shared area over which the impact is dispersed (e.g. hitting something pointy is not good), and the weight of the rider. This may bear little relationship to the forward speed of the bicycle in its direction of travel for anything other than a head on collision.

Doozerie's static fall is a good example of this. If you fall sidewards on a bike that is not moving forward, you're effectively pivoting about point at which wheels touch the ground, and will hit hard as angle of incidence will be close to 90 degrees. If you're travelling forward when you come off the bike, the angle of incidence will most likely be much smaller, so your initial impact will be a glancing blow hopefully followed by a roll or skid.

Practising and teaching a fair bit of wrestling in the past, you get to learn pretty quickly that if you've got any momentum at all when been thrown and can use that momentum to roll, you'll pick up much less damage. Sticking an arm out (AKA posting) is a natural reaction, but certainly in wrestling a very poor one, as it will typically get you a broken wrist or dislocated shoulder or elbow. Relaxing, curling up slightly (tucking), and moving with the throw tends to give the best outcome. No idea whether or not this translates to cycling, though it does work well with hard surfaces when wrestling.

RainyDay

Beasty wrote: »

One of my accidents was in the UK. I've never seen that website and suspect a large majority of those involved in an accidents are oblivious to it. Equally as no motor vehicle was involved in either accident the police and Gardai showed little if any interest in either

It's a brand new site, just launched this week.
http://sustainablecitiescollective.com/david-thorpe/1004871/collideoscope-new-open-data-app-aiming-cut-cycling-accidents

smacl

tomasrojo wrote: »

A collection of anecdotes about helmets would be mostly about things that don't happen very often.

But a significantly sized collection of similar anecdotes can suggest a trend which deserves further more systematic investigation.

CramCycle

My own personal reactions to crashes are at slow speed I tend to jut out my arms and they sting like the blazes with sore wrists for weeks after. At high speed, natural reaction takes over and I seem to lift my arms to either brace my neck or cover my face which puts me in a nice shape for rolling. For me helmets make this more awkward to do, which is why i think that any speedy crashes I have had seem to be alot less severe in terms of injury than slow speed ones.

Of course, I could do a Beasty on it and well, have a garmin showing full speed to stationary in less than a second.

This is why anecdotes are terrible points of reference as we never give the in depth detail to outsiders to let them decide or analyse the true issues, we may not even know what they were and more importantly we definitely don't know how the presence or absence of any one specific factor would altered the situation and our reaction in such a situation so as to be able to even come close to judging whether that one factor would have had a positive or negative effect.

The one thing we do know is that looking at the meta analysis (OK, briefly skimming over), is that there seems to be no benefit but also no downside to wearing a helmet at societal level in terms of injury rates and/or their severity.

Apologies for the stupidly long sentences.

magicbastarder

tomasrojo wrote: »

No, that's the problem: an anecdote is a memorable story. Data is systematically collected observations, both mundane and extraordinary, collected by someone who doesn't distinguish, or preferrably is unable to distinguish (blind studies).

A collection of anecdotes about helmets would be mostly about things that don't happen very often.

this is the rub; how do you collect such data without constant monitoring of cyclists - which is difficult or expensive to do?
i'd be interested to hear how much data is collected by self-reporting by cyclists, in which case the 'anecdotes' would form a large part of the data set.

doozerie

magicbastarder wrote: »

i saw mention above that there would be no poll on helmets, which i found puzzling; it's not scientific, but given there's a lot of interested cyclists on this forum, it's be interesting to learn if (for example, i'm not trying to pre-empt a possible result) on the whole the reaction would be 'i believe that a helmet has saved me from more serious injury than i actually did suffer'.

I see the real value of this thread being in how it promotes discussion around helmets, their perceived benefits/risks, innovation in helmet design, potential consequences of laws relating to helmets, public conceptions/misconceptions about helmets, etc. Polls don't promote discussion, all too often, by their nature they can actually tend to stifle discussion.

If 99% of poll respondents chose the option that said "my helmet saved my life" that would tell me nothing about the true effectiveness, or not, of helmets and the thread would risk dissolving into a meaningless "you're wrong, I'm right because most of the respondents voted for the same option as me" argument. Personally I find this thread informative on many levels, I'd hate to see it turn into what might essentially end up being a stick with which to beat people of whatever minority view was represented in the poll.

RainyDay

magicbastarder wrote: »

this is the rub; how do you collect such data without constant monitoring of cyclists - which is difficult or expensive to do?
i'd be interested to hear how much data is collected by self-reporting by cyclists, in which case the 'anecdotes' would form a large part of the data set.

This new UK service would seem to offer a solution to collecting such data in structured format and eliminating the drama and emotion

http://www.boards.ie/vbulletin/showpost.php?p=92632199&postcount=1150

RayCun

Still the problem of self-selection. People are more likely to bother reporting incidents with serious consequences, either medical or financial

magicbastarder

that's still self-reporting, though.

are there any figures for the extent of helmet use in ireland? i.e. based on someone standing on dame street counting cyclists, rather than depending on the sort of people interested enough in cycling to self-report, such as on this forum, for example?

magicbastarder

RainyDay wrote: »

This new UK service would seem to offer a solution to collecting such data in structured format and eliminating the drama and emotion

http://www.boards.ie/vbulletin/showpost.php?p=92632199&postcount=1150

the bit i was getting at earlier regarding anecdotes being part of data is only potentially useful if you're trying to determine how useful helmets are in a crash.

but it is no use whatsoever at capturing information about whether a cyclist's behaviour might change, or other road users' behaviour might change, based on whether the cyclist is wearing a helmet.

tomasrojo

smacl wrote: »

But a significantly sized collection of similar anecdotes can suggest a trend which deserves further more systematic investigation.

Yes, I think that can be true. Such as the peasants who used to tell incredulous gentlemen scientists about rocks that fell out of the sky, which turned out in the end to be from space.

magicbastarder wrote: »

this is the rub; how do you collect such data without constant monitoring of cyclists - which is difficult or expensive to do?
i'd be interested to hear how much data is collected by self-reporting by cyclists, in which case the 'anecdotes' would form a large part of the data set.

There is a very approximate method, which is to look at, say, national trends and statistics. These should show up very large effects, but not modest ones. You need a second group to compare with. In the case of bicycle helmets, you can compare cyclist trends with pedestrian trends to get some idea of what part of an improvement or disimprovement in head injury rates is down to a general increase in road safety, since this should also benefit pedestrians.

Self-selection is a recognised problem in case-control studies (e.g the misleading initial results of the HRT studies, which mistook the benefits of having a high-ish income for the benefit of HRT). Self-report studies are worse, I think. Apart from subjectivity (about what respondents include and exclude in their accounts), there can also be systematic differences between those who choose to get involved and those who don't, resulting in bias.

tomasrojo

magicbastarder wrote: »

that's still self-reporting, though.

are there any figures for the extent of helmet use in ireland? i.e. based on someone standing on dame street counting cyclists, rather than depending on the sort of people interested enough in cycling to self-report, such as on this forum, for example?

There was a European report that had Ireland's wearing rate at 40%. Highest in Europe, as far as I recall. (Jersey is alleged to have a stratospherically high rate, which I'd believe, but these were national figures.

http://www.etsc.eu/documents/ETSC_2011_PIN_Report.PDF

magicbastarder

would be interesting if that was before or after the dublin bike scheme, which would extert a downward pressure on the figures.

tomasrojo

magicbastarder wrote: »

would be interesting if that was before or after the dublin bike scheme, which would extert a downward pressure on the figures.

That's a really good point. I think the Cycle to Work scheme might have put upward pressure at about the same time though (a lot of people getting bikes for around €500-800, wrung the last bit of change out by getting a helmet).

I should explain that last bit in parentheses: I think when people who had been using an old bike for years decided to upgrade because of the scheme, some of them may have decided to get a helmet for the first time or the first time in a while then.

NeedMoreGears

I like this thread.

I wonder if a lot of the pro/con discussion gets a bit confused by the expectations that people have regarding the performance of cycling helmets. To (grossly) generalise and (perhaps unfairly) divide people into three camps:

Group A : Helmets are essential and convenient safety equipment that will save your life. You will definitely die without one!

Group B: If you get hit by a truck at 40kph a helmet is useless. Helmets are a complete waste of time!

Group C: There's no compelling evidence at the population level in either direction. What will I do?

As I understand it, helmets offer reasonable injury reduction benefits in low to moderate energy collisions between the wearer's head and a hard surface. For me that's sufficent reason to wear one. I get to avoid stitches and maybe a concussion in the event of a fall. That effort/reward ratio may not sufficiently persuasive for others but I'll wear a helmet anyway. On the other hand I don't find the hi-viz risk effort/reward compelling (not wishing to derail the thread!)

NeedMoreGears

galwaycyclist wrote: »

Also this



So helmets may be having a protective effect in crashes but at the cost of an increased risk of being in a crash at all.

Could that not be due to the possibility that cyclists who tend to travel a higher speeds perceive a greater risk and are seekign to mitigate that risk by wearing a helmet?

magicbastarder

i had to laugh at noonan's response to a question about the VAT rate applied to bike helmets; 'paperwork':

http://debates.oireachtas.ie/dail/2011/10/25/00079.asp

CramCycle

magicbastarder wrote: »

i had to laugh at noonan's response to a question about the VAT rate applied to bike helmets; 'paperwork':

http://debates.oireachtas.ie/dail/2011/10/25/00079.asp

While MB helmets were zero rated from the 70s, the 0% rate on bicycle helmets for over 10s in the UK only came into action in 2001 from my understanding.

Here: SI 2001/732. Under section 30(4) of VATA 1994, amendments to any of the descriptions used in Schedule 8.

galwaycyclist

NeedMoreGears wrote: »

Could that not be due to the possibility that cyclists who tend to travel a higher speeds perceive a greater risk and are seekign to mitigate that risk by wearing a helmet?

Yes

tomasrojo

Chris Boardman being taken to task by Headway:
https://aseasyasridingabike.wordpress.com/2014/11/04/headways-brick-wall/

And he replies:
http://www.britishcycling.org.uk/campaigning/article/20141103-campaigning-news-Boardman--Why-I-didn-t-wear-a-helmet-on-BBC-Breakfast-0

Jawgap

How safe is cycling?

http://www.bbc.com/news/magazine-29878233

TL/DR - cycling is safe.

Iwannahurl

tomasrojo wrote: »

Chris Boardman being taken to task by Headway:
https://aseasyasridingabike.wordpress.com/2014/11/04/headways-brick-wall/

If Headway UK (and Ireland) want to significantly reduce the risk of Acquired Brain Injury, they could start by not organising fundraising events centred on the consumption of alcohol.

http://www.headway.ie/support/fundraisingeven/2014/04/03/spritz-time-italian-aperitifs-and-nibbles/

Headway Ireland fundraising suggestions: http://www.headway.ie/download/doc/az_of_fundraising.doc

Get sponsored to give up alcohol

Or maybe do the opposite, such as organising drinking games:

Wine & cheese party – homemade wine, prizes and cheese donated. Guess the wines country game. Charge admission and for entering games.

.

ford2600

NeedMoreGears wrote: »

I like this thread.

I wonder if a lot of the pro/con discussion gets a bit confused by the expectations that people have regarding the performance of cycling helmets. To (grossly) generalise and (perhaps unfairly) divide people into three camps:

Group A : Helmets are essential and convenient safety equipment that will save your life. You will definitely die without one!

Group B: If you get hit by a truck at 40kph a helmet is useless. Helmets are a complete waste of time!

Group C: There's no compelling evidence at the population level in either direction. What will I do?



As I understand it, helmets offer reasonable injury reduction benefits in low to moderate energy collisions between the wearer's head and a hard surface. For me that's sufficent reason to wear one. I get to avoid stitches and maybe a concussion in the event of a fall. That effort/reward ratio may not sufficiently persuasive for others but I'll wear a helmet anyway. On the other hand I don't find the hi-viz risk effort/reward compelling (not wishing to derail the thread!)

Group No idea what a helmet might or might not do for them but keeps loved ones happy and stops strangers bothering them with their opinions of PPE on the side of the road/coffee stop