Irresponsible Ad

On Sat, 02 Jul 2005 12:27:46 -0400, Mike Tennent
wrote:

Sorry, if I had realised that you didn't have the faintest clue about
risk compensation theory I'd have explained it more clearly. For a
good basic grounding I suggest you read Target Risk by Wilde
(http://psyc.queensu.ca/target/), or Risk by Adams.

Perhaps you should re-read it and try to apply the principles
logically.

No need. I have read that, and other books on risk compensation, and
had a long chat with John Adams who is an authority on the matter. He
is strongly against helmet compulsion and both he and Gerald Wilde are
patrons of the Bicycle Helmet Research Foundation. I am on he
Editorial Board.

Remember that crashes are caused, in the main, not by the taking of
large risks, but by the taking of small risks very large numbers of
times. Cycling crashes are rare, you see, and serious injuries rarer;

LOL. Guess you've never ridden in a crit.

Even if that were relevant to the generic issue of cycling and
helmets, which it clearly isn't any more than Indy 500 is relevant to
everyday driving, the same principles apply. Riders in mass-start
races have very high levels of bike control skills, and can ride fast
and close. One rider pre-compulsion asked the team manager to "pass
my helmet, I'm feeling aggressive today". And more pro riders have
died in races in the last five years than in any previous decade
(small samples, YMMV, yada yada). The point about the cliff walk
applies here, too. Racers can walk right along the cliff edge in fair
safety, due to their great skills, but if they move an inch closer,
skills or no, the risk still increases. And in racing there is always
an incentive to be closest to the edge. In fact, if you don;t want to
be closes to the edge you probably don't race in the first place.

It's a bit like walking along near the edge of a cliff. The risk of
falling over gets higher the closer you go to the edge, even though
the change in risk for each successive inch closer to the edge is
unmeasurably small.

Ok, let's apply this principle to helmet use. In this thread you've
blamed helmet wear for a higher rate of injury - not the activity
itself.

And based on nothing more than the evidence for many countries
including the USA - shocking ;-)

Every sanctioning body in the US involved in bicycle racing - road,
off-road, triathlon, etc mandate helmet use.

And often on very tenuous grounds. I remember an exchange recently
where the policy was blamed on insurance, but the insurers later said
they had made no such stipulation.

These individuals are
constantly involved in higher risk competition and higher risk
training (speed and course) - far more than the casual joe citizen on
his beach cruiser who doesn't wear a helmet. We're talking about a
factor of thousands of times more risk exposure. And their accidents
are far more likely to be reported.
Don't you think that just might skew the numbers?

Undoubtedly.

But no, you say statistics prove that it's because they wear a helmet
that they have a higher risk. You blame the safety equipment, not the
far higher risk exposure. That's a hoot.

No, because I don't say that. What I say is that, judging from the
figures I have, there appear to be more and worse crashes in racing
now everyone wears a helmet. This is in line with the well-documented
theory of risk compensation.

You are also adding context which was absent from the original
statements, which involved helmets and motor vehicles.

Of course, it's easy to prove just about anything if you ignore cause
and effect.

Correct. Every pro-helmet study of which I'm aware does exactly that.

Children who are breast fed are less likely to be injured in car
accidents. Do you think this is because of nutrition or because of
lower numbers in the population?

You are talking to the wrong man about that. I am very aware of the
effects of socioeconomic confounding on injury trends.

http://www.cyclehelmets.org/mf.html#1052

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

88% of helmet statistics are made up, 65% of them at CHS, Puget Sound

(Tom Keats) writes:

In article ,
(Bill Z.) writes:
l (Tom Keats) writes:


In other words, his helmet didn't work.

Helmets are designed for impacts against more or less flat objects,
like the surface of a road.

Good grief. Even a statement like the above gets a big reaction from
these anti-helmet nuts.

The only times I've heard of cyclists squarely hitting
the road head-first were when they were hit from behind
by cars with such force as to launch them straight up;
snip of details of such accidents

This is red herring. Being hit from behind is very rare but with a
high fatality rate, and hitting the road "squarely" is not relevant.
The vertical component of your head's velocity is what determines the
impact, with the horizontal component being relevant to the amount of
abrasion.

The high fatality rate for being hit from behind is not surprising as
typically the driver doesn't notice the cyclist at all when this
happens - otherwise the driver would have slowed down or swerved, and
the high impact speeds increase the chance of fatality.

then they arc back down again with a trajectory like
that of a V2 rocket, and the cyclists landing head-first
on the road behind the cars that hit them. Although
sometimes they land on top of the car. Of those riders
who were wearing helmets, theirs didn't work either.

Are you trying to pretend that people don't ever fall off their bikes
and simply hit the road? It would be rather hard for you to pretend,
after all, that a road is not basically a flat surface, since most
readers would only have to walk away from their monitors and look out
the nearest window to refresh their memories if that were for some
reason necessary.

--
My real name backwards: nemuaZ lliB

"Just zis Guy, you know?" writes:

On Sat, 02 Jul 2005 12:27:46 -0400, Mike Tennent
wrote:


Of course, it's easy to prove just about anything if you ignore cause
and effect.

Correct. Every pro-helmet study of which I'm aware does exactly that.

Or rather, any study that shows a benefit for helmet use, no matter
how small, is suspect in Guy's mind. You'll get the same reaction
if you talk about carbon dating to someone who thinks the earth
is only a few thousand years old.

--
My real name backwards: nemuaZ lliB

At Sat, 02 Jul 2005 18:50:30 GMT, message
was posted by
(Bill Z.), including some, all or none of
the following:

Of course, it's easy to prove just about anything if you ignore cause
and effect.

Correct. Every pro-helmet study of which I'm aware does exactly that.

Or rather, any study that shows a benefit for helmet use, no matter
how small, is suspect in Guy's mind.

LOL! Whereas Bill will not allow any statement which is not wholly
uncritical of helmets, however well supported by evidence!

In this case, I can back my statement with as many quotations from the
studies as you like. I said: every pro-helmet study of which I'm
aware ignores cause and effect; I stand by that. Can you cite one
which doesn't?

You'll get the same reaction
if you talk about carbon dating to someone who thinks the earth
is only a few thousand years old.

LOL! Last week British doctors were given a figure for deaths fifty
times too great, quotes the 88% figure, told that observational
studies were randomised clinical trials and assured that dropping a
watermelon in a helmet was an appropriately scientific model for the
efficacy of helmets. And yet it is the sceptics - those who say
"prove it!" - who Bill accuses of being zealots!

Thanks for some laughs there, Bill.

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

"Just zis Guy, you know?" writes:

At Sat, 02 Jul 2005 18:50:30 GMT, message
was posted by
(Bill Z.), including some, all or none of
the following:

Of course, it's easy to prove just about anything if you ignore cause
and effect.

Correct. Every pro-helmet study of which I'm aware does exactly that.

Or rather, any study that shows a benefit for helmet use, no matter
how small, is suspect in Guy's mind.

LOL! Whereas Bill will not allow any statement which is not wholly
uncritical of helmets, however well supported by evidence!


Typical of Guy's lies. He has no valid argument and resorts to trying
to put words in people's mouths. And of course Guy's "evidence" is
primarily whether Guy likes the results or not.


In this case, I can back my statement with as many quotations from the
studies as you like. I said: every pro-helmet study of which I'm
aware ignores cause and effect; I stand by that. Can you cite one
which doesn't?

Why bother? Any time anyone posts a result that shows even the most
minor benefit for a helmet, you'd claim it must be garbage. I once
asked you to point to *any* study that actually measured a benefit
to helmet use, no matter how small, and you couldn't provide one,
and the probability of the benefit being precisely zero is
astronomically low. As usual, you are morphing "insufficient data"
into a claim about helmets.


You'll get the same reaction
if you talk about carbon dating to someone who thinks the earth
is only a few thousand years old.

LOL! Last week British doctors were given a figure for deaths fifty
times too great, quotes the 88% figure, told that observational
studies were randomised clinical trials and assured that dropping a
watermelon in a helmet was an appropriately scientific model for the
efficacy of helmets. And yet it is the sceptics - those who say
"prove it!" - who Bill accuses of being zealots!

Care to give a citation for this claim? Of course, we could substitute
this alleged watermellon with your head. Would that make you happy?

It would certainly improve this newsgroup considerably.


Thanks for some laughs there, Bill.

More lies from Guy.

--
My real name backwards: nemuaZ lliB

Mike Tennent wrote:
On 1 Jul 2005 08:05:44 -0700, wrote:


Do you decapitate yourself as you fall?


LOL. No, but I thought it was fairly obvious that there would be
little or no difference between an attached head hitting the concrete
at 12 mph and a "detached" head hitting the concrete at 12 mph. the
brain stops just as suddenly.

Ah. So the mass and inertia of the body behind the head has no effect
at all? Interesting!

IOW, if we strap a bike helmet on a round wooden headform and drop it,
then strap a bike helmet on the end of a 20 foot telephone pole and
drop it, the effect would be the same?

Personally, I believe the mass of the body attached to the head would
certainly have an effect. I believe it would require greater force to
decelerate than the decapitated head. And I know that typical bike
helmets are at their absolute limit trying to decelerate that
decapitated headform at less than 300 gees.

I think this is one reason that bike helmets have been shown to be
useless in large population studies. There are other reasons, to be
sure, but this one is not negligible.

And I also assumed that you made that irrelevant distinction based
upon the testing techniques.

I'm not sure what you meant by that sentence. Are you admitting that
you don't know what the testing techniques are?

- Frank Krygowski

At Sat, 02 Jul 2005 21:11:24 GMT, message
was posted by
(Bill Z.), including some, all or none of
the following:

Of course, it's easy to prove just about anything if you ignore cause
and effect.
Correct. Every pro-helmet study of which I'm aware does exactly that.
Or rather, any study that shows a benefit for helmet use, no matter
how small, is suspect in Guy's mind.
LOL! Whereas Bill will not allow any statement which is not wholly
uncritical of helmets, however well supported by evidence!

Typical of Guy's lies.

In the Vandeman sense of the word, obviously.

In this case, I can back my statement with as many quotations from the
studies as you like. I said: every pro-helmet study of which I'm
aware ignores cause and effect; I stand by that. Can you cite one
which doesn't?

Why bother?

Ah: you can't. Thought not.

Any time anyone posts a result that shows even the most
minor benefit for a helmet, you'd claim it must be garbage. I once
asked you to point to *any* study that actually measured a benefit
to helmet use, no matter how small, and you couldn't provide one,
and the probability of the benefit being precisely zero is
astronomically low. As usual, you are morphing "insufficient data"
into a claim about helmets.

Insufficient data? Like Rodgers, eight million cases over 15 years?

If there is "insufficient data" to show that helmets do nothing then
there is sure as hell "insufficient data" to show they do anything
meaningful!

LOL! Last week British doctors were given a figure for deaths fifty
times too great, quotes the 88% figure, told that observational
studies were randomised clinical trials and assured that dropping a
watermelon in a helmet was an appropriately scientific model for the
efficacy of helmets. And yet it is the sceptics - those who say
"prove it!" - who Bill accuses of being zealots!

Care to give a citation for this claim?

BMA Annual Representative Meeting, Manchester, 30/6/05.

Of course, we could substitute
this alleged watermellon with your head. Would that make you happy?

No, that would require substituting it with your head. Or Vandeman's.

Thanks for some laughs there, Bill.
More lies from Guy.

BillZYou have a webcam in my house? How do you know if I'm
laughing? You know nothing about what makes me laugh!/BillZ

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

"Just zis Guy, you know?" writes:

At Sat, 02 Jul 2005 21:11:24 GMT, message
was posted by
(Bill Z.), including some, all or none of
the following:

Of course, it's easy to prove just about anything if you ignore cause
and effect.
Correct. Every pro-helmet study of which I'm aware does exactly that.
Or rather, any study that shows a benefit for helmet use, no matter
how small, is suspect in Guy's mind.
LOL! Whereas Bill will not allow any statement which is not wholly
uncritical of helmets, however well supported by evidence!

Typical of Guy's lies.

In the Vandeman sense of the word, obviously.

Odd how you bring Vandeman up all the time. In fact you seem obsessed
with him.


In this case, I can back my statement with as many quotations from the
studies as you like. I said: every pro-helmet study of which I'm
aware ignores cause and effect; I stand by that. Can you cite one
which doesn't?

Why bother?

Ah: you can't. Thought not.

As I said ...



Any time anyone posts a result that shows even the most
minor benefit for a helmet, you'd claim it must be garbage. I once
asked you to point to *any* study that actually measured a benefit
to helmet use, no matter how small, and you couldn't provide one,
and the probability of the benefit being precisely zero is
astronomically low. As usual, you are morphing "insufficient data"
into a claim about helmets.

Insufficient data? Like Rodgers, eight million cases over 15 years?

Which 8 million are you talking about this time? At one point, you
referred to the population of an area, not the number of crashes
(which is probably why you just gave an author and not a proper
citation).

See
http://www.dft.gov.uk/stellent/groups/dft_rdsafety/documents/page/dft_rdsafety_507998-07.hcsp#TopOfPage
and go to the bottom for 'prev/next' links to different parts of the full
report.

BTW, when I asked you what sample size you considered adequate, you
declined to proivde a simple number, and we know why that is.

If there is "insufficient data" to show that helmets do nothing then
there is sure as hell "insufficient data" to show they do anything
meaningful!

If you'll check, I've consistently only argued your claims (and those
of the other usual suspects) *against* helmets basically turned null
results due to insufficient data into a claim that helmets don't work
at all.


LOL! Last week British doctors were given a figure for deaths fifty
times too great, quotes the 88% figure, told that observational
studies were randomised clinical trials and assured that dropping a
watermelon in a helmet was an appropriately scientific model for the
efficacy of helmets. And yet it is the sceptics - those who say
"prove it!" - who Bill accuses of being zealots!

Care to give a citation for this claim?

BMA Annual Representative Meeting, Manchester, 30/6/05.

Now post the actual text. BTW, the only thing I could find in a quick
Google search was
http://www.bikebiz.co.uk/daily-news/article.php?id=5712 which
stated, "It may only be planned to be a five minute affair ..."

Since the meeting was only held the day before yesterday and it may
have been only 5 minutes long, why don't you post a transcript?

Of course, we could substitute
this alleged watermellon with your head. Would that make you happy?

No, that would require substituting it with your head. Or Vandeman's.

I think yours will do, as there is nothing in it worth saving.

--
My real name backwards: nemuaZ lliB

writes:

Mike Tennent wrote:
On 1 Jul 2005 08:05:44 -0700, wrote:


Do you decapitate yourself as you fall?


LOL. No, but I thought it was fairly obvious that there would be
little or no difference between an attached head hitting the concrete
at 12 mph and a "detached" head hitting the concrete at 12 mph. the
brain stops just as suddenly.

Ah. So the mass and inertia of the body behind the head has no effect
at all? Interesting!

If the "mass an inertial of the body behind the head" was important in
the typical bicylce crash, the likely outcome would be a broken neck.

rest of Krygoswki's troll snipped.


--
My real name backwards: nemuaZ lliB

Bill Z. wrote:
writes:

Mike Tennent wrote:
On 1 Jul 2005 08:05:44 -0700, wrote:


Do you decapitate yourself as you fall?


LOL. No, but I thought it was fairly obvious that there would be
little or no difference between an attached head hitting the concrete
at 12 mph and a "detached" head hitting the concrete at 12 mph. the
brain stops just as suddenly.

Ah. So the mass and inertia of the body behind the head has no effect
at all? Interesting!

If the "mass an inertial of the body behind the head" was important in
the typical bicylce crash, the likely outcome would be a broken neck.

If you're going to quote me, Bill, do it accurately. For example, keep
your misspellings for your own sentences - don't inject them into mine.

And, since an ordinary person can (with training) support his entire
weight in a headstand, it follows that the force on a helmet in at
least some crashes would be greatly influenced by the mass of the body
attached to the head. Again, think of putting a helmet on one end of a
telephone pole and dropping it on the ground. Even if you "neck down"
the section of pole 12" from the helmet, the mass of the pole causes
more damage to the helmet.


- Frank Krygowski