On Wed, 27 Aug 2008 10:47:15 +0100, "Dave Larrington"
wrote:

In ,
judith tweaked the Babbage-Engine to tell us:

No authoritative body in the UK recommends not wearing cycle helmets,
as their is no evidence that wearing them is more dangerous than not
wearing them.
Many authoritative bodies do in fact recommend wearing them.

Any body which ignores the evidence which suggests that the wearing of
helmets makes cycling /more/ dangerous has, at best, a highly dubious claim
to being "authoritative".


Yes you are right - the DfT and RoSPA are not authoritative in any
sense of the word - neither are any of the cycle clubs who insist that
their members wear them. You'll be telling me that the cycle clubs
don't understand cycling next !!

(Unlike the very balanced cyclehelmet.org)

Here are some gems against helmets:

The main - and worst - thing they do is discourage cycling.

Cycle helmets can increase the probability of some injuries through
increasing the radius of the head and thus increasing the likelihood
of a strike and the longer lever arm to cause higher rotational
acceleration, and thus brain injury.

Even the promotion of cycle helmets leads to the dangerisation of
cycling, and puts people off.

A helmet will increase the radius of the head and so increase the
torque applied if the helmeted head hits the ground. Additionally it
will increase the risk of the head actually hitting the ground.

I think the best one is from the ****wit Chapman : "you can either
promote cycling or promote helmets,the two are incompatible.


--
I encourage my children to wear helmets. (Guy Chapman)
Some evidence shows that helmeted cyclists are more likely to hit
their heads. (Guy Chapman)
I have never said that I encourage my children to wear helmets. (Guy
Chapman) (Indeed, this was an outright lie)

In ,
judith tweaked the Babbage-Engine to tell us:

Yes you are right - the DfT and RoSPA are not authoritative in any
sense of the word - neither are any of the cycle clubs who insist that
their members wear them. You'll be telling me that the cycle clubs
don't understand cycling next !!

Probably because they've not bothered to examine the data properly, just
listened to the strident squealings of the pro-compulsion lobby.

Cycling != helmet use.

--
Dave Larrington
http://www.legslarry.beerdrinkers.co.uk
You can't have ham!

On 26 Aug, 23:54, judith wrote:

No authoritative body in the UK recommends not wearing cycle helmets,

Correct. No bodies that I am aware of recommend not wearing them. I
know one or two individuals who recommend not wearing them but there
are very few people who actively recommend not wearing them for normal
road cycling.

... as their (sic) is no evidence that wearing them is more dangerous than not
wearing them.

There is compelling evidence that, at the population level and in
terms of deaths and serious injuries, there is no benefit when wearing
rates are greatly increased. There is strong evidence that rates of
death and serious injury increase when the wearing rate is greatly
increased. There is compelling evidence that the numbers of people
cycling reduce significantly when helmet wearing is made compulsory.

There is plenty of evidence that helmets greatly reduce the incidence
of certain classes of minor injury. Mile for mile the risk of serious
injury when cycling is about the same as when walking. In terms of
life expectancy it is certainly safer to cycle with or without a
helmet than not to cycle [1]. This is why helmet wearing should be
left as a choice for the individual. Helmets in themselves are not
bad. In circumstances where minor injuries are likely it may make
sense to wear a helmet, particularly for indivduals who are nervous of
them or likely to be discouraged by them. Helmet compulsion or
aggressive helmet promotion, however, will always lead to an increased
rate of death or serious injury and a reduction in public health due
to the reduced numbers cycling.

Many authoritative bodies do in fact recommend wearing them.

Indeed they do.

--
Dave...

On Wed, 27 Aug 2008 10:47:15 +0100, Dave Larrington wrote:

In ,
judith tweaked the Babbage-Engine to tell us:

No authoritative body in the UK recommends not wearing cycle helmets,
as their is no evidence that wearing them is more dangerous than not
wearing them.
Many authoritative bodies do in fact recommend wearing them.

Any body which ignores the evidence which suggests that the wearing of
helmets makes cycling /more/ dangerous has, at best, a highly dubious claim
to being "authoritative".

Exactly.

"judith"'s position is that as these organisations have a name that starts
with CAPITAL LETTERS, what they say must be true.

Unlike her name, of course...

On 27 Aug, 12:14, dkahn400 wrote:

In terms of life expectancy it is certainly safer to cycle with or without
a helmet than not to cycle [1].

I forgot to add my footnote. It should have been:

[1] The trade-off for a cyclist is to accept a very small chance of
serious injury or a greatly reduced life span in return for a very
large chance of a significantly increased life span with a healthier
and more active old age.

--
Dave...

In message
judith wrote:

On Tue, 26 Aug 2008 14:40:04 -0700 (PDT), Eric
wrote:

On 26 Aug, 22:31, judith wrote:

Because I do not have the ability to plough through and digest all of
the currently available evidence - as I have said.

You insist on arguing from a state of ignorance?


I for one admit to not being able to understand all of the research
papers on cycle helmets; I suspect that I am with the majority of the
population there.

It is a failing of much of the population including many professionals.
Sadly the teaching of mathematics is not given the priority that it
should be given and even many science graduates and medical
practitioners have a poor grasp of statistics.

Let me try to illustrate the dangers of extrapolation from a case study
using an example from outside of cycling.

It has been observed that within the UK population those who have
graduated with a University degree on average tend to end up in
professions with a higher salary. Thus there is an observed association
between income and the degree qualification. Now some politicians and
government ministers, as well as journalists and many members of the
population, have latched onto that association and have turned it into a
causal association. Having a university degree will lead to higher paid
employment. So the next logical step is to get more and more school
leavers to go to university and gain a degree qualification.

So what happens as the percentage of the population having a degree
qualification gets higher and higher? Does everyone end up benefiting to
the same extent as graduates did before? Or do we still have some people
earning more than others except that the degree qualification is no
longer as important in determining the association? Will competition for
jobs mean that employers will start to use other means to select amongst
applicants who now all have a degree qualification?

The mistake made here is to assume that the only thing that
distinguishes the two groups in the initial sample is the opportunity to
go to university and study for a degree. Also the assumption is that the
availability of higher paid professions is unlimited and that if you
have more qualified people the employment opportunities expand in exact
proportion. (i.e. they are linearly scaleable). Clearly this simplistic
modelling is wrong and you can't extrapolate easily between the before
and after scenarios.


So let's return to cycle helmets. If you work in a hospital accident and
emergency unit you might study those cyclists who are admitted for
treatment and you might compare those who were wearing cycle helmets on
admission with those who were not. You might also take note of the
proportion of cyclists in the general population who wear helmets. That
analysis might lead you to the conclusion that there is an association
between wearing helmets and lesser injuries on average.

But are the two populations of helmet wearers and non-wearers identical
in all other respects, except for the wearing of helmets? Do they have
similar incomes, similar temperaments, ride similar bicycles, are they
of a similar age and socio-economic group? Was their decision to
purchase and wear a helmet a random decision without any other factors
coming into play?

If the voluntary decision to purchase and to wear a cycle helmet is not
random there is immediately a danger that studying a small
sub-population of helmeted wearers is a biased study and that it may not
be possible to scale the results in a linear fashion to the whole
population if you subsequently made wearing compulsory rather than
voluntary.



You, no doubt, have digested all of them and come to an independent
conclusion

Yes I personally have. I do have an advantage that my professional work
involves researching new drugs and thus I spend a lot of time analysing
the results from different kinds of clinical trials, some case
controlled, some randomised, some double blinded and randomised, and
others retrospective population studies.

that cycle helmets are dangerous - well done!

You have once again misinformed yourself with an incorrect narrative
interpretation of what has been relayed to you.

The population studies show that the introduction of compulsory wearing
of cycle helmets is not associated with a general reduction in the rates
of severe cycle injuries. That is emphatically not the same as saying
"cycle helmets are dangerous", (although it doesn't rule that
possibility out either).


Mike
--
M.R. Clark PhD, Reader in Therapeutic and Molecular Immunology
Cambridge University, Department of Pathology
Tennis Court Road, Cambridge CB2 1QP
Tel +44 (0)1223 333705 Web http://www.path.cam.ac.uk/~mrc7/

On 27 Aug, 09:35, judith wrote:
On Tue, 26 Aug 2008 14:58:37 -0700 (PDT),Squashme



wrote:
On 26 Aug, 21:56, judith wrote:
On Tue, 26 Aug 2008 11:01:53 -0700 (PDT),Squashme

wrote:
On 26 Aug, 18:39, judith wrote:
On Tue, 26 Aug 2008 12:09:10 +0100, Mike Clark
wrote:

snip

That last paragraph is not one that I would dispute, but I'd go much
further and say that a better training of everyone (pedestrians,
cyclists and motorists) in the Highway Code, and also in the underlying
laws of use of PRoWs would be to the benefit of all.

Mike

Until someone produces some easy to understand explanation as to why
cycle helmets do not give you additional protection - the vast
majority of people will continue to believe that they are better than
no helmet.

That may be a basis for individual choice. It is not a basis for
legislation to make wearing helmets compulsory.

Are you not worried that cyclists with helmets will be more dangerous
for pedestrians than cyclists without? Risk compensation encouraging
higher pavement speeds, for instance.

No - do you have the results of research which shows that cyclists
with helmets are more likely to break the law and cycle on pavements
and cause accidents with pedestrians than those without?

No, do you have the results of any research which shows the contrary?

Are you new to usenet - that's not the way things work. You state
something - people ask you for a cite. It's considered the wimps
attempt at a way out to ask for the opposite.

I did not STATE it, I asked whether you were worried by the
possibility.


You are asserting that it will be more dangerous for pedestrians when
cyclists are wearing helmets - just back it up.

However I did raise the possibility of risk compensation.


It may be worth looking at the effects of seat-belt legislation on
pedestrians and cyclists, rather than motorists.

I don't think it was.

Why not write to the DfT and tell them they have the seat belt
legislation wrong and we should go back to the free for all.


I would prefer intelligent seat-belts that became less protective as
their motorist's speed increased. This would provide feedback, and a
positive eugenic effect.
Perhaps built-in breathalysers would be useful too. Why over-protect
the guilty from the consequences of their own actions?

Seatbelts did not improve the free-for-all as far as pedestrians and
cyclists were concerned.

On Wed, 27 Aug 2008 11:15:08 GMT, _
said in
:

"judith"'s position is that as these organisations have a name that starts
with CAPITAL LETTERS, what they say must be true.

It's a fairly straightforward case of the "appeal to authority"
fallacy. Having been confronted with evidence, analysis and
numerous people who are manifestly better informed than she, judith
has fallen back on the tried and tested "but doctors say..."
argument. We all know that "doctors" is here semantically
equivalent to "former medical students", and the campaign of
disinformation from the helmet lobby has been long and often highly
successful, thanks in no small part to generous funding from the
manufacturers.

I checked the publication list for Dr. Commonsense and found that
virtually everything he's published has since been proven to be
complete ********. That appears to be judith's main source here.

Guy
--
May contain traces of irony. Contents liable to settle after posting.
http://www.chapmancentral.co.uk

85% of helmet statistics are made up, 69% of them at CHS, Puget Sound

On Mon, 25 Aug 2008 08:46:17 +0100, judith wrote:

On Sun, 24 Aug 2008 13:47:23 +0100, "Just zis Guy, you know?"
wrote:

On Sat, 23 Aug 2008 15:25:52 +0100, judith
said in :

This will be an objective assessment of cycle helmets from the
organisation who have stated their message as / raison d'etre :
"Helmets are not beneficial to cyclists".

Really? I wonder why this "message / raison d'etre" is not
mentioned anywhere on the policy statement?

I believe that they have stated it in the past - I am happy to accept
that they do not state it now if you say that they don't.

I am sorry if I was wrong.

(This - by the way is termed an apology - I realise it may be a word
not in your vocabulary)


And in consequence, you clearly now agree that the evidence presented IS an
objective assessment.

Thankyou.

"judith" wrote in message
...
On Tue, 26 Aug 2008 19:34:19 +0100, "Michael C"
wrote:

You keep dodging the points and questions. I gave you two links to the
two
sides of the argument earlier.


I have read some of the links - I do not have the time,the
inclination, or the ability to plough through papers where I suspect
that some of the research may have been carried out with a required
result in mind. You only have to look at cyclehelmets.org and the CTC
to see that the way that the information is presented is biased.
Indeed, Chapman brags that he is on the editorial board of
cyclehelmets.org but his unbiased view is that you can either promote
cycling or promote helmets,the two are incompatible. I have been told
that cyclehelmets.org was originally set up to give the message that
helmets were not a good thing. (I accept that they do not publicly
state this now)

Like it or not - one of the strongest arguments by the anti-helmet
brigade is that compulsory wearing of helmets will reduce the number
of cyclists - therefore, they say, compulsory helmets are a bad thing.

And what is wrong with saying that? It is merely one argument among many as
to why helmets should not be made compulsory.

The DfT and RoSPA have their own biases yet you willingly take what they say
as gospel.

You are someone who wants cycle helmets to be compulsory - yet you have
not
offered one bit of evidence or proof that they reduce the amount of
injuries
to cyclists. Why is this?

Because I do not have the ability to plough through and digest all of
the currently available evidence - as I have said. I will therefore
rely on the advice of the DfT and RoSPA.

You have already said that you read some of the links - when they say that
there is no evidence that wearing a helmet makes you safer, do you not
believe them?

You can object all you like but : - there are plenty of authoritative
organisations who do recommend wearing cycle helmets.

And there are others that don't recommend it either way. What is your
point
here?

That the majority of people if asked would say that cycle helmets
provide more benefit than harm; and that cycle helmet compulsion will
come.

What has what the majority of people got to do with this? Do you make
decisions based on what the facts show or on what people think is true?

I would be interested in the "authoritative" bodies who recommend NOT
wearing cycle helmets - are there any - can you tell me please?

I don't think there are any but I don't see how this is relevant. They
might say that they leave the choice up to the rider, but they wouldn't say
you shouldn't actually wear one.