Helmet worked for me

[pjclinch]

Have ROSPA studied the costs/benefits of helmets for car passengers?
(They are at least as significant a source of head injuries as those from cyclists.)

What's the question that this would answer?

JDSK chat assistant: How can I help?
mattheus: <ok, I'll try again ...> What have ROSPA published on the subject of helmets to reduce head injuries in cars?

JDSK chat assistant: I'm the JDSK chat assistant, I think you may want RoSPA for that...

(I note that "studying the cost benefits" and "publishing anything" may not be entirely the same thing, and my impression is this is part of why Jonathan is very clear about the importance of setting out one's questions carefully)

Pete.

[mattheus]

(I note that "studying the cost benefits" and "publishing anything" may not be entirely the same thing, and my impression is this is part of why Jonathan is very clear about the importance of setting out one's questions carefully)

Pete.

Very true: and of course I endorse the value of asking precise questions!

But anyway; is there a reason not to answer this simple question? (we are not an academic publishing body, nor are we in a court of law:we're just here to have a polite constructive debate. I hope ... )


What have ROSPA published on the subject of helmets to reduce head injuries in cars?

[Cugel]

.......the importance of setting out one's questions carefully)

Pete.

Very true: and of course I endorse the value of asking precise questions!

But anyway; is there a reason not to answer this simple question? (we are not an academic publishing body, nor are we in a court of law:we're just here to have a polite constructive debate. I hope ... )

The trouble with precise questions is that they'll contain precise answers - and because every question tends to define the small range of permissible answers (by defining permitted terminology, concepts and even fact-structures) precise terms mean the range of permissible answers is greatly reduced.

This problem with language is as old as human history. It can be quite difficult for us to break out of habitual modes of thinking, mental perspectives and other modes that exclude a whole range of explanations of things .... because we use a limited set of words in a particular language hosted in a particular cultural milieu.

In many ways, academics are the most captured by this syndrome. They have specialist languages used in small communities of those qualified to do so. A favoured methodology of investigation can become ossified or ideologically-required, as can a set of assumptions of what is set as an unassailable truth, fact or process for discovering this or that.

*******

The cycling helmet issue is a perfek example of just how hard it is to separate the subjective assumptions of the investigators from the objective occurrences in the real world. The two are inevitably meshed in a way that makes it impossible for any human to discover any clear boundary between them. There is no such boundary.

There's a tendency to look also for universal answers. "Do helmets protect all cyclists from some harms"? There is no such thing as "all cyclists" except as a language construct. In reality there's a vast range of cyclists, cycling habits/modes and environments in which they ride. This is true for a vast range of human activities.

So, what may be appropriate or of utility for person A with riding habits B in environment C is of itself quite a big perm. For millions of cyclists following a subset of hundreds of cycling habits in thousands of environments, the perm is huge.

No singe use-case for helmets and no simple answer, then. Ditto for a great number of other human doings.

On the other hand, some activities contain incontrovertible causes and effects. Much H&S lore is derived to help with such circumstances. (It's always good to wear insulating clothes of functionality grade F when walking across the tundra for ten miles at -25 degrees C). Cycling is no such easy case.

[pjclinch]

^^^^
I'm pretty much onside with this, though I note that while tightly defined questions will give highly contextual answers that are less useful than we might like, at least that's better than vaguely defined questions that are assumed to have universal answers where none beyond the like of "it depends" exist (e.g., "is a vegetarian diet healthy", "is democracy a good form of government", "should I wear a cycle helmet?" etc. etc.)

So, ask a carefully qualified/contextualised/nuanced question about helmets and get a carefully qualified/contextualised/nuanced answer, or ask a vague question (or make an overly sweeping statement) about helmets and get a flame war

Pete.

[drossall]

That "ought to be visible" needs to be supported by a fair bit of reasoning and calculation...

I'm grateful for the response because I do try to keep some kind of open mind. But I'm not sure where to go with that advice. I have some understanding of what you mean by the PICO headings (physics degree but absolutely no special qualifications or experience relevant to the immediate topic, other than decades of cycling). But I'm not clear whether you're suggesting that what I said is wrong, or only applies in certain conditions, or whether the unknowns are simply too large to say anything? And if the last of these, how is that different from what I said?

[Jdsk]

That "ought to be visible" needs to be supported by a fair bit of reasoning and calculation...

I'm grateful for the response because I do try to keep some kind of open mind. But I'm not sure where to go with that advice. I have some understanding of what you mean by the PICO headings (physics degree but absolutely no special qualifications or experience relevant to the immediate topic, other than decades of cycling). But I'm not clear whether you're suggesting that what I said is wrong, or only applies in certain conditions, or whether the unknowns are simply too large to say anything? And if the last of these, how is that different from what I said?

I was suggesting that "ought to be visible" is a very interesting assertion and that the PICO approach would be helpful and appropriate in exploring it. And I'd encourage you to do just that: there's plenty of *support available on the relevant methods. And it would be particularly interesting if you felt able to do it in this forum.

Jonathan

* Sources available if needed.

[Cugel]

That "ought to be visible" needs to be supported by a fair bit of reasoning and calculation...

I'm grateful for the response because I do try to keep some kind of open mind. But I'm not sure where to go with that advice. I have some understanding of what you mean by the PICO headings (physics degree but absolutely no special qualifications or experience relevant to the immediate topic, other than decades of cycling). But I'm not clear whether you're suggesting that what I said is wrong, or only applies in certain conditions, or whether the unknowns are simply too large to say anything? And if the last of these, how is that different from what I said?

PICO seems to be a procedural methodology used in medicine - one so vague in its terms that it allows the insertion of whatever specifics suit the current notions of the medical PR actioner using it to give a semblance of "doing things scientifically".

It's perhaps a step or two better than the often wild guessing or habitual diagnosing employing some fixed ideas seen in many GPs .... but not a lot.

PICO is, though, a good illustration of how a lump of invented talky stuff can give a sheen of "logic and rationality" to the doings of a profession seeking to give an impression of infallibility when it is, in fact, guessing or employing often hackneyed notions enjoying a degree of popularity and tenure within a profession.

*************
Any endeavour that seeks to measure and understand (and perhaps predict) human behaviours has a seemingly insurmountable difficulty. The human mind is a structure inclined to form a whole host of notions that can be of more or less utility in dealing with the world. They're also complicated immensely by the overlay of language and the vast cultural edifices it creates and installs into our brain processes. It's hard for the human mind to understand the human mind.

This mind imposes structure on whatever reality is, with its small subsection of effects made available to us via our senses. It imposes some rather queer structures on reality, once the mind is infested with large and complex cultural constructions such as religions and philosophies. Science too is fundamentally a philosophy; it too imposes a lot of what turns out to be queer stuff that's far from having utility (except in upholding the status of some group that uses it as a belief-badge or qualification of worth).

Here's a very interesting article about the human mind and an oblique (to the norms of Western culture) attempt to understand its workings better:

https://nautil.us/finding-peter-putnam- ... 1354232454

[pjclinch]

PICO is a common approach, but as Goldacre and Spiegelhalter pointed out...

With regard to the use of bicycle helmets, science broadly tries to answer two main questions. At a societal level, “what is the effect of a public health policy that requires or promotes helmets?” and at an individual level, “what is the effect of wearing a helmet?” Both questions are methodologically challenging and contentious.

The devil, as often the case, turns out to be in the detail, and with a PICO approach to investigating cycle helmet efficacy particularly in the way that the intervention (the helmet) is very, very hard to untangle from the wearer such that one can easily compare two populations where nothing except the intervention changes, so that differences in outcomes can be attributed solely to the intervention.

People have been trying to apply PICO approaches to cycle helmet efficacy for decades and still haven't come up with solid conclusions. There may be "plenty of support available on the relevant methods", but I think a professor of evidence based medicine probably knew about them before putting his name to "methodologically challenging and contentious" in an editorial that kinds of throws up its hands in despair at the all the variables that need untangling.

Back to RoSPA and their numbers, it's really for them to justify better than "here are some numbers we found" if they're making claims.

Pete.

[Jdsk]

In case anyone here doesn't know already, that's a reference to:

"Bicycle helmets and the law":
https://www.bmj.com/content/346/bmj.f38 ... eytype=ref

And it's well worth reading what else he (and Spiegelhalter ) has to say about evidence-based policy making.

Jonathan

[cyclist]

'm supporting Pete on this one.... its up to you to to decide whether or not to wear a helmet based on the risks and hazards that the journey presents...
...where I tend to draw the line is the almost subconscious thought that ' I wear a helmet therfore I am safe' which is a dangerous thought...
..being 'safe' or a degree thereof starts with basic bike control, understanding the hazards of the environment in which you ride, placing yourself to minimise such hazards, correctly predicting the future actions of those around you...and so on... wearing a helmet is a long way down the list, and if you're sharing a road with motor traffic

Thank you for clarification. I do not believe that I subscribe to 'I wear a helmet therefore I am safe'. While the helmet helped take the impact of my fall. It did not stop me from getting concussed, and it did not stop my body from getting bruised.

[Cugel]

'm supporting Pete on this one.... its up to you to to decide whether or not to wear a helmet based on the risks and hazards that the journey presents...
...where I tend to draw the line is the almost subconscious thought that ' I wear a helmet therfore I am safe' which is a dangerous thought...
..being 'safe' or a degree thereof starts with basic bike control, understanding the hazards of the environment in which you ride, placing yourself to minimise such hazards, correctly predicting the future actions of those around you...and so on... wearing a helmet is a long way down the list, and if you're sharing a road with motor traffic

Thank you for clarification. I do not believe that I subscribe to 'I wear a helmet therefore I am safe'. While the helmet helped take the impact of my fall. It did not stop me from getting concussed, and it did not stop my body from getting bruised.

Risk compensation, whereby we take more risks than a new safety thing can justify, is a very slippery and persistent little head-worm. Even we who are very conscious of it can find ourselves nevertheless behaving just a bit too riskily.

Last year I bought a full e-car to replace the hybrid e-car. The hybrid was a bit of a lumbering e-guzzler and could run out of go ,,so demand petrol, after 25 hilly miles. This encouraged slow and careful driving, to husband the e but with the side effect of driving more safely (slower and with a further gawp down the road coming up so as to judge regen brake switching and so forth).

The new e-car is far more efficient with the e, which is also free to us from the large solar panel array on our roof. We didn't buy it because it's very vroomy .... but it is. Amazing acceleration, braking and cornering.

So, I tried very hard not to be seduced but it seduced me anyway for a few weeks. I drove a bit faster, especially around corners.

Happily (I think that's the right word) I came across an incident where another driver going far too fast through a village just missed a ped in the road (there are no pavements in this village) 'round a bend. This has brought me to my senses. That could've been me! The nice brakes and cornering don't make the human a better driver. They generally make us worse.

Beware the seductive protector! They have their limits and they're not as good as the adverts and scuttlebutt suggest.

[drossall]

I was suggesting that "ought to be visible" is a very interesting assertion and that the PICO approach would be helpful and appropriate in exploring it. And I'd encourage you to do just that: there's plenty of *support available on the relevant methods. And it would be particularly interesting if you felt able to do it in this forum.

I've already admitted to not being especially qualified. What I have been doing is following the debates for forty years now. The earliest publication I have come across, before even the famed Thompson and Rivara, was something in the Journal of Products Liability in 1988, that raised questions. Although to be fair I know nothing of the editorial standards of that journal, it has never struck me as one likely to have a helmet agenda either way. And of course all the stuff that's appeared in the BMJ over the years.

So, if as already mentioned Goldacre and Spiegelhalter can't sort it out, I'm inclined to go with them rather than think that I as an amateur can sort out what the professionals cannot.

If you asked me to summarise what I've seen, it's confusing. Broadly, research seems to divide into hospital studies or similar, looking at who comes into casualty departments, and population-level studies. Both have so many confounding factors as to be very difficult as sources of cast-iron conclusions. Probably though, hospital studies trend toward benefit, although with some outliers. Wasn't there a Danish nurse who did a study in one hospital and showed an annual benefit in that one location in excess of the total head injuries suffered by the entire national cycling population?

Meanwhile national trends are difficult because of problems in recording, factors such as other legislation introduced at the same time as mandatory helmets. Often, one bill will both make helmets compulsory and reduce speed limits. [The same politicians will then claim the same injury reductions as entirely a result of either one of the two measures and others, depending on which they are currently being questioned about.] But I have seen some impressive time series showing the tendency for cycle and pedestrian casualty rates to follow the same trends, and that the introduction of cycle helmets, but not those for pedestrians, has made no perceptible difference to that.

Essentially my point was that, the larger the claims of benefit made, the greater the difficulty in explaining why it's so hard to see anything in the national trends. Bluntly, if as many people as now claim to have been saved by their helmets were suffering death and serious head injury back before helmets were a thing, cycling would have been far, far more dangerous than it is now. But it simply wasn't.

Sorry, not a bit of PICO in that.And, as I said, if Goldacre and Spiegelhalter can't solve it, why should I be able to?

[Stevek76]

Meanwhile national trends are difficult because of problems in recording, factors such as other legislation introduced at the same time as mandatory helmets. Often, one bill will both make helmets compulsory and reduce speed limits. [The same politicians will then claim the same injury reductions as entirely a result of either one of the two measures and others, depending on which they are currently being questioned about.]

Further complicated because countries introducing helmet laws generally aren't serious about cycling as a mode of transport and so weren't collecting much data on it in the first place.

But I have seen some impressive time series showing the tendency for cycle and pedestrian casualty rates to follow the same trends, and that the introduction of cycle helmets, but not those for pedestrians, has made no perceptible difference to that.

Indeed helmet campaigner Jake Olivier relies on dismissing the data behind such timeseries as not robust. I thought I recalled a paper of his where he does more detail on these but can't find it with a quick search, just some more recent ones where hand waves it away as not being a problem.

Curiously one of those does unironically quote a US study finding a 'slight' reduction of 3-5% in children cycling as a result. A 3-5% reduction in cycling rates replicated in the UK would generate considerable net public health disbenefits even if helmets were 100% effective against all possible acute harm through lost activity levels, let alone knock on secondary impacts.

[pjclinch]

...if Goldacre and Spiegelhalter can't solve it, why should I be able to?

Indeed, and even if I had the skills I don't have particularly easy access to the data I'd need, and even if I had that I frankly doubt I'd have the time to do a proper job.

I'm left with looking for smoking guns fired by specialists, where my skill set has a chance of following others' work that I can't do myself. So far the smoke I've come across claimed to be from guns tends to be of the "and mirrors" variety.

Pete.

[Cugel]

AT the time that cycle helmets of the more modern kind began to appear (end of the 1980s, beginning of the 90s) I was of the road dacing and TTing ilk, as well as a sometime tourist. Such helmets rapidly became mandated for racing but most cast them side when not racing. At the time, there was the experience fresh in the minds of habitual cyclists, even ones riding fast & close, that head injury risks were rare.

For some, though, a helmet had more appeal as an every-ride item as their personal history contained head-bang events (usually more than one, in fact .... several). Such a choice for them was obviously sensible, even if they did sometimes assume the helmet provided more protection than it did.

Over time, as helmets became more heavily promoted and fashionable, this inclination of many experienced cyclists to reference their personal history, rather than the fashion when choosing whether to wear a helmet or not, faded. Along with the fashion-driven decision came the usual after-the-fact rationalisations. No one wants to feel they were just a fashion victim, eh!?

Today it's become difficult to use personal cycling history to make a judgement about helmet-or-not. Many I know feel a fear of going for a ride without one - even those who did so for decades before 1990. It really is astonishing how powerful adverts, fashion and the human need for conformity can make us do things that are either unnecessary or, in some cases, actually harmful to us.

Helmet-harms are perhaps insignificant to the potential harms of, say, voting for a Farrago ..... but there are some. Risk compensation is probably the worst; just being uncomfortable in the thing is the least.

*********
How to do the risk assessment today? Well, as we ever did before studies and their data - try to use personal history and an estimate of how one as a particular human with a particular set of bodily abilities and inclinations would invoke various kinds of risks in various kinds of circs.

If I cycled daily through a heavily urbanised environment full of potholes, kerbs and upright street furniture, I would be inclined to wear a helmet as the risk of a fall and bang of the head on a sign-pole or similar would seem a distinct possibility. Maybe MTBing through a forest ..... . Happily, I have to do neither.