Ontario Helmet Law being pushed through

On Fri, 31 Dec 2004 01:15:17 GMT, (Bill Z.)
wrote in message :

That, my good man, is the point - we are comparing helmeted
versus unhelmeted cyclists and you want to eliminate extraneous variations
between cyclists so you can obtain meaningful data about helmets as
used in practice.

And eventually, if we wait long enough, the penny will finally drop in
Bill's head that this is precisely the problem with most of the
pro-helmet studies.

Actually it is the major problem with most of what you cite (although
it is often your side of the usenet discussion that is causing the
distortions.)

Really. And your evidence for that is? Have you read the 1989
Seattle paper yet? It is very clear from the detail of that paper
that they have made precisely the error I describe: ascribing to
helmets the difference in behaviour between completely different
groups of cyclists.

Spaite states that: "A striking finding was noted when the group of
patients without major head injuries (246) was analyzed separately.
Helmet users in this group still had a much lower mean ISS (3.6 vs.
12.9, p less than 0.001) and were much less likely to have an ISS
greater than 15 (4.4% vs. 32.1%, p less than 0.0001) than were
nonusers. In this group, 42 of 47 patients with an ISS greater than 15
(89.4%) were not wearing helmets. We conclude that helmet nonuse is
strongly associated with severe injuries in this study population.
This is true even when the patients without major head injuries are
analyzed as a group; a finding to our knowledge not previously
described."

So now you will cite a pro-helmet study which eliminates extraneous
variables. And I don't mean the usual method of elimination in
observational studies, making a guess, I mean a pro-helmet study which
actually controls out the other factors.

The closest I've seen is the time-trends from New Zealand and
Australia, where the major source of confounding is the loss of a
large group of occasional cyclists from the figures. Just to refresh
your memory, an analysis of the effect of increased wearing in New
Zealand concluded: "increased helmet wearing [...] has had little
association with serious head injuries to cyclists as a percentage of
all serious injuries to cyclists for all three groups [children,
adolescents and adults], with no apparent difference between bicycle
only and all cycle crashes. Discussion of the results includes
possible explanations for the absence of a decline in the percentage
of serious head injury among cyclists as cycle helmet wearing has
increased." (Trends in cycle injury in New Zealand under voluntary
helmet use, Scuffham PA, Langley JD, 1997. Accident Analysis and
Prevention: 1997 Jan;29(1):1-9). The author was also unable to prove
a cost benefit for helmets on the basis of reduced healthcare costs.

So, please do go ahead and cite the study which you think controls out
the extraneous factors. Bear in mind that the pro-helmet lobby is
doing the selling here, so necessarily carries the burden of proof.

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

I've been riding bikes (racing) since 1989, and I've had more near misses
when I *AM* wearing my lid then when I have chosen not to when its 30+
degrees outside in Winnipeg... seems that people think because you are
wearing some sort of "protection" they can inch that little bit closer to
ya...

While I'm ranting here, I wonder if ANY car driver who is not a cyclist
releizes that some people on bikes can and do travel the same speed as
traffic or faster at times...

Chris


"Frank Krygowski" wrote in message
...
R15757 wrote:

Frank K. wrote:


Show us the numbers you want to use. Perhaps we can discuss them.


Why don't we start by discussing the numbers
you have been posting. Approximately one
fatality every four million hours according to
the infamous Design News/Failure Analysis car
fire chart[1]. Working backward, we see that
Failure Analysis Associates is claiming
something like 3.2 billion hours of total cycling
occurs each year in the US[2]. Wow! That's
a lot of cycling! How did they figure that out?

That would be like the entire population of the
US riding 8 hours per year. Or 32 million cyclists
riding 100 hours. Personally, I tend to believe that
the real figure is probably about half that at best.
There is not much good data available to help
us determine what that figure is. Consider,
however, that cycle-commuters are known to
comprise 1-2% of US workers. It seems that,
at most, commuter cycling would total no more
than one billion hours per year. You might get
another billion hours from all the kids' and
recreational riding combined. In the end, total
cycling hours are probably less than half of
what FAA claimed, and therefore our precious
fatality rate should probably be doubled, not
that it matters much. Of course my numbers
are a shot in the dark as well, but at least I
told you where I came up with them, which puts
me way ahead of Failure Analysis Associates.

Robert
1. Design News, October 4, 1993.
2. Based on approximately 800 fatalities
per year.

:-) Ah, I see. It seems to _you_ that commuting would be no more than
one billion hours. And it seems to _you_ that all kids and all
recreational riding would total another billion hours. That's what it
seems to _you_.

To recap, then, you say the National Safety Council figures are bogus.
"I don't know if it's high or low, neither
do you or the Nat'l Safety Council."

And you say "To me, your numbers appear to be based on JACK SQUAT."

Of course, some readers may be confused about how "It seems to YOU"
differs from "based on JACK SQUAT." :-)




FWIW, http://www.bicyclinglife.com/Library/SteppingStones.htm alludes to
the difficulties of counting hours of cycling. And he mentions
comparisons of cycling vs. driving, per hour for various European
countries. The agencies gathering data in some of those countries find
cycling to be safer than motoring; most are roughly equal, and some are
more dangerous.

But as the author (Malcolm Wardlaw) points out, even in "more dangerous"
Britain, cycling is VERY safe by any absolute measurement.


So the bad news for you, Robert, is that this "cycling is safe"
conspiracy goes far beyond the people at Failure Analysis Associates
(the largest risk consultation firm in the country, with over 100 PhDs
studying such questions), and beyone the National Safety Council (who
are in business to give warnings of danger whenever possible). It
extends even to other countries in the world!

If you're going to convince the world that cycling is extremely
dangerous, you've got work to do!

Here's a suggestion: You could add a signature file to your posts.
Something like "Cycling is about as dangerous as driving!!!" You could
attach the footnote "It seems to me."

That should strike fear in people's hearts! ;-)


--
--------------------+
Frank Krygowski [To reply, remove rodent and vegetable dot com,
replace with cc.ysu dot edu]

"Just zis Guy, you know?" writes:

On Fri, 31 Dec 2004 01:10:42 GMT, (Bill Z.)
wrote in message :

And risk compensation (e.g. Risk compensation in children?s
activities: A pilot study, Mok D, Gore G, Hagel B, Mok E, Magdalinos
H, Pless B. 2004. Paediatr Child Health: Vol 9 No 5 May/June 2004)

You said:

Risk compensation is not obviously applicable to helmet use due to the
lack of protection against road rash and other unpleasant effects of a
crash.

Our survey said:

"CONCLUSION: The results indicate that risk compensation may
modify the effectiveness of PE for children engaged in sports and
leisure activities. Conversely, the findings also suggest that those
wearing PE may be a cautious subgroup."

We were talking specifically about bicycle helemts, which do not
prevent road rash to areas not covered by the helmets, nor do the
helmets protect a rider from injuries such as a broken hip. It is
simply not clear that a bicycle helmet has anything significant to do
with risk compensation---the chances of falling so that the head is
the only thing that might be injured is negligible.

But I'd be delighted to see your hard evidence for suggesting that the
use of cycle helmets is uniquely immune to this otherwise apparently
universal phenomenon. With citations, please, you know how I like to
collect papers.

You are making the claim. It is up to you to back it up. I'll give
you a hint, though. Beef up the strength of a roll bar in a
convertable and see if that has any impact on driving. It won't: what
does have an impact includes better handling - better steering and
braking. People generally want to avoid painful injuries and
expensive property damage. Covering the head alone while cycling does
no such thing. If anything, it makes the injuries more painful to the
extent that the victim remains conscious.


--
My real name backwards: nemuaZ lliB

"Just zis Guy, you know?" writes:

On Fri, 31 Dec 2004 01:13:50 GMT, (Bill Z.)
wrote in message :

An excellent example of fitting ad-hoc arguments to facts which don't
support the chosen premise.

Oh nonsense. The factor of 5 is documented in _Effective Cycling_,

Note that Guy cut what I said mid-sentence. That's a sure sign that
he needed to hide what I really said in order to make up a reply.

But is irrelevant in context, because what you are doing (as stated)
is dreaming up ad-hoc arguments to explain away the observed facts:
(a) there is no country in the world where cyclist safety is
positively correlated with helmet use and (b) the studies which
contain enough data to analyse properly, consistently show that the
helmeted and unhelmeted rider communities behave sufficiently
differently as to make comparison impossible without large-scale
assumptions.

If, as Guy now claims, "the helmeted and unhelmeted rider communities
behave sufficiently differently as to make comparison impossible
without large-scale assumptions," then it follows that any of the
population-based studies he touts are inadequate for measuring
helmet effectiveness.

Rather than dreaming up ad-hoc arguments to explain this away, I
prefer to apply Occam's Razor and conclude, as the Australian
transport safety board has recently agreed, that helmets are
essentially irrelevant as a road safety measure.

I'll snip the rest. Anything beginning with that is obviously a rant.

Translation: "Laa laa I'm not listening".

Translation - rhetorical excess is not a valid argument, and you
will be ignored, including the rest of your posts today. You are
obviously back in infantile troll mode.
snip

--
My real name backwards: nemuaZ lliB

On Sat, 01 Jan 2005 20:06:33 GMT, (Bill Z.)
wrote in message :

"CONCLUSION: The results indicate that risk compensation may
modify the effectiveness of PE for children engaged in sports and
leisure activities. Conversely, the findings also suggest that those
wearing PE may be a cautious subgroup."

We were talking specifically about bicycle helemts

As were the authors of that study.

It is
simply not clear that a bicycle helmet has anything significant to do
with risk compensation---the chances of falling so that the head is
the only thing that might be injured is negligible.

So you say, and the cited study disagrees, explicitly for the case of
cycle helmets. I note you have provided no evidence to back your
assertion that cycle helmets are uniquely immune from this widespread
phenomenon. The balance of evidence is against you at this point.

You are making the claim. It is up to you to back it up.

No, Bill, I am not selling anything except scepticism. The burden of
proof remains with those pushing product - in this case helmets.

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 Sat, 01 Jan 2005 20:13:25 GMT, (Bill Z.)
wrote in message :

Note that Guy cut what I said mid-sentence. That's a sure sign that
he needed to hide what I really said in order to make up a reply.

It is not necessary to repeat your argument in order to point out that
it is a typical example of Liddites coming up with any explanation
they can find for the fact that helmets do not reduce injuries in
whole populations - any explanation, that is, other than the obvious
one suggested by Occam's Razor.

If, as Guy now claims, "the helmeted and unhelmeted rider communities
behave sufficiently differently as to make comparison impossible
without large-scale assumptions," then it follows that any of the
population-based studies he touts are inadequate for measuring
helmet effectiveness.

It is not my claim, it is Spaite's. But no matter. Once you have
converted the entire cyclist population (to a first approximation)
into helmet wearers, you have in fact removed the majority of the
confounding, so whole population and time-series studies are less
prone to this problem than the tiny hospital based studies on which
helmet campaigns are based.

But please do tell which pro-helmet studies eliminate all confounding.
There must surely be some. You know how I like to collect papers and
evidence, and would be something entirely new to me: a pro-helmet
study which does not suffer from the self-selection problems which are
currently causing a crisis in epidemiology, according to a learned
colleague of mine.

rhetorical excess is not a valid argument,

We noticed. I live in hope that one day you will post some evidence.

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

Bill Z. wrote:

Would you claim there is any significant difference in Condi's versus
Donald's views in a context where the opposing viewpoint is provided
by Noam Chomsky? That's like quibbling about the difference in
position between the earth and the moon in a discussion about galactic
features 10 kiloparsecs in size. To claim there is any significant
difference in the viewpoints of Krygowksi et al. in a comparision with
mainstream views on the subject is equally absurd.

So therefore you can criticize Frank for something Tom said? Sorry, I
don't buy it, and I doubt anyone else does.

--
Benjamin Lewis

Seeing is deceiving. It's eating that's believing.
-- James Thurber

"Bill Z." wrote in message
...
"Just zis Guy, you know?" writes:

On Fri, 31 Dec 2004 01:10:42 GMT, (Bill Z.)
wrote in message :

And risk compensation (e.g. Risk compensation in children?s
activities: A pilot study, Mok D, Gore G, Hagel B, Mok E, Magdalinos
H, Pless B. 2004. Paediatr Child Health: Vol 9 No 5 May/June 2004)

You said:

Risk compensation is not obviously applicable to helmet use due to the
lack of protection against road rash and other unpleasant effects of a
crash.

Our survey said:

"CONCLUSION: The results indicate that risk compensation may
modify the effectiveness of PE for children engaged in sports and
leisure activities. Conversely, the findings also suggest that those
wearing PE may be a cautious subgroup."

We were talking specifically about bicycle helemts, which do not
prevent road rash to areas not covered by the helmets, nor do the
helmets protect a rider from injuries such as a broken hip. It is
simply not clear that a bicycle helmet has anything significant to do
with risk compensation---the chances of falling so that the head is
the only thing that might be injured is negligible.


The same argument would presumably apply to motorcycle helmets as well,
which obviously do nothing to protect against road rash or broken bones
either (other than the skull). Nonetheless, as I pointed out in an earlier
post, there seems to be some pretty solid evidence that risk compensation
must be taking place to explain the enormous differences in the apparent
effectiveness of motorcycle helmets observed among the various states
related to whether a universal mandatory helmet law is in place or not, and
how well such a MHL may or may not be enforced.

Riley Geary

"Riley Geary" writes:

"Bill Z." wrote in message
...
"Just zis Guy, you know?" writes:
snip
We were talking specifically about bicycle helemts, which do not
prevent road rash to areas not covered by the helmets, nor do the
helmets protect a rider from injuries such as a broken hip. It is
simply not clear that a bicycle helmet has anything significant to do
with risk compensation---the chances of falling so that the head is
the only thing that might be injured is negligible.


The same argument would presumably apply to motorcycle helmets as well,
which obviously do nothing to protect against road rash or broken bones
either (other than the skull). Nonetheless, as I pointed out in an earlier
post, there seems to be some pretty solid evidence that risk compensation
must be taking place to explain the enormous differences in the apparent
effectiveness of motorcycle helmets observed among the various states
related to whether a universal mandatory helmet law is in place or not, and
how well such a MHL may or may not be enforced.

The same argument may apply to motorcycle helmets, but your counter
example does not, since it involves mandatory helmet laws and
traffic-law enforcement. What you are ignoring includes:

* state legislatures typically work in "fire drill" mode
and don't pass things like a MHL unless there is a perceived
problem. A perceived problem usually requires either a high
accident rate or a tragic accident involving a child or
teenager.

* law enforcement is similarly driven. If there is not a
perceived issue to be addressed, you don't get stepped up
law enforcement.

Due to that, you can't draw conclusions about helmet effectiveness
based on a comparison of states with and without a MHL and with
differing levels of enforcement if you merely look at the accident
rates.

--
My real name backwards: nemuaZ lliB

Benjamin Lewis writes:

Bill Z. wrote:

Would you claim there is any significant difference in Condi's versus
Donald's views in a context where the opposing viewpoint is provided
by Noam Chomsky? That's like quibbling about the difference in
position between the earth and the moon in a discussion about galactic
features 10 kiloparsecs in size. To claim there is any significant
difference in the viewpoints of Krygowksi et al. in a comparision with
mainstream views on the subject is equally absurd.

So therefore you can criticize Frank for something Tom said? Sorry, I
don't buy it, and I doubt anyone else does.

I didn't. Frank was purposely misinterpretting what I had said by
pretending that "you guys" referred to him and him alone. If either
of you don't understand the normal use of a plural noun, I suggest
a remedial course in English.

Benjamin, why don't you just grow up. If you've been following this
thread, as you seem to claim, you'd know damn well what Frank was
doing. Posting distorted statements like your statement above,
in the hopes of misleading people who haven't followed the thread,
is just plain bad form on your part.

--
My real name backwards: nemuaZ lliB