published helmet research - not troll

"Just zis Guy, you know?" wrote in message
news
On Sun, 20 Jun 2004 16:04:19 GMT, "Shayne Wissler"
wrote in message
7AiBc.85246$Sw.42132@attbi_s51:

The helmet research I've seen so far is junk--it focuses on population
statistics not physics, and is motivated to social change not truth.

For varying values of "junk" - small scale prospectiuve studies are
certainly prone to error, but whole population evidence is harder to
ignore. That's what proved the link between smoking and cancer.

It's not the same thing. Different helmet designs are going to have
different effects. Those statistics completely ignore that factor. And
people who wear helmets might be more cautious anyway, or less skillful,
which would distort the statistic one way or the other. Without a
cause-effect analysis, the statistics--on both sides of the argument--are
worthless junk. With the social agenda bias in either direction they should
be ignored.

If researchers really cared about the truth of the matter, they would
take
some of this casual analysis and more and begin formulating good models
for
this so they'd have more to go by than mere emergency room statistics,
and
also have a means of specifying better helmets. Maybe the manufacturers
do
this, I don't know.

The manufacturers don't care a damn as far as I can tell. They have
pushed through lower standards and it's almost impossible to find a
helmet made to Snell B95.

Snell B95 isn't the standard. The right standard is a good physical model
built from causal analysis and experiment.

Most manufacturers probably make what they think they can sell instead of
making the best they can create. Since the public is largely uncritical and
apathetic to real science, and many businessmen are cynical and deaf to the
better part of the public (which I think can be successfully appealed to),
some or all of the manufacturers may not bother with the verifiable and
instead come up with designs that are good enough to make a buck off of or
that are pretty or mainly designed for comfort--the aspects of design that
most people can relate to.

If I'm being overly harsh then point me to the manufacturer who has a good
research paper published on this topic.


Shayne Wissler

"Frank Krygowski" wrote in message
...
Shayne Wissler wrote:

The helmet research I've seen so far is junk--it focuses on population
statistics not physics, and is motivated to social change not truth.

If researchers really cared about the truth of the matter, they would
take
some of this casual analysis and more and begin formulating good models
for
this so they'd have more to go by than mere emergency room statistics,
and
also have a means of specifying better helmets. Maybe the manufacturers
do
this, I don't know.

I seriously doubt the manufacturers do anything that won't improve their
bottom line!

Of course, they can improve their bottom line by giving money to Snell,
which can give money to Safe Kids Inc. and various lobbyists, who can
lobby legislators to mandate their products, whether or not they work!

A good example of how the current form of government distorts what should be
a free market.

But manufacturers charge over $150 for gossamer-thin racing helmets that
have significantly less impact protection than average bike helmets,
while still (barely) passing the test standards.

Clearly, they're not in the protection business; they're in the business
of selling helmets.

Assuming a free market, it would be in a helmet manufacturers best interest
to be in the business of both, for the same reasons. In the current
mixed-economy it still makes sense for a helmet manufacturer to be
principally concerned with the performance of the helmet and to let profits
flow from that--it's the only honest way, and it in fact still could lead to
becoming a market leader.


Shayne Wissler

On Sun, 20 Jun 2004 17:13:03 GMT, "Shayne Wissler"
wrote in message
zAjBc.81468$HG.13644@attbi_s53:

For varying values of "junk" - small scale prospectiuve studies are
certainly prone to error, but whole population evidence is harder to
ignore. That's what proved the link between smoking and cancer.

It's not the same thing. Different helmet designs are going to have
different effects. Those statistics completely ignore that factor. And
people who wear helmets might be more cautious anyway, or less skillful,
which would distort the statistic one way or the other. Without a
cause-effect analysis, the statistics--on both sides of the argument--are
worthless junk. With the social agenda bias in either direction they should
be ignored.

For varying values of "worthless" :-D

Fundamentally, we agree: the science at present is poor. It lumps
riding round the park with extreme downhill and trundling to the
corner shop with RAAM. The only thing I can see from the
whole-population stats is that focusing on helmets is probably a wste
of time, since risk lowest where helmet use is lowest and highest
where helemt use is highest, so helmets don't seem to be a good
candidate if you want to find the best thing to make cycling safer.

Numbers cycling, on the other hand, correlates well with improving
safety. I don't suggest that the relationship is necessarily causal,
but there are plausible mechanisms by which it could be. I think
promoting cycling is a much better bet if you want to improve safety.
But then, I'm a cyclist - I would say that, woudln't I?

The manufacturers don't care a damn as far as I can tell. They have
pushed through lower standards and it's almost impossible to find a
helmet made to Snell B95.

Snell B95 isn't the standard. The right standard is a good physical model
built from causal analysis and experiment.

True enough. There isn't one. Snell is nearer that than EN1078 or
CPSC certification though.

Most manufacturers probably make what they think they can sell instead of
making the best they can create. Since the public is largely uncritical and
apathetic to real science, and many businessmen are cynical and deaf to the
better part of the public (which I think can be successfully appealed to),
some or all of the manufacturers may not bother with the verifiable and
instead come up with designs that are good enough to make a buck off of or
that are pretty or mainly designed for comfort--the aspects of design that
most people can relate to.

I entirely agree.

If I'm being overly harsh then point me to the manufacturer who has a good
research paper published on this topic.

Bell fund the Safe Kids campaign - does that count? Thought not.

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 Washington University

On Sun, 20 Jun 2004 17:17:39 GMT, "Shayne Wissler"
wrote in message
TEjBc.149003$Ly.90993@attbi_s01:

Assuming a free market, it would be in a helmet manufacturers best interest
to be in the business of both, for the same reasons. In the current
mixed-economy it still makes sense for a helmet manufacturer to be
principally concerned with the performance of the helmet and to let profits
flow from that--it's the only honest way, and it in fact still could lead to
becoming a market leader.

Why bother when you can use dodgy statistics and emotional blackmail
to coerce the government into mandating the existing, flawed product?

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 Washington University

"Just zis Guy, you know?" wrote in message
...
On Sun, 20 Jun 2004 17:17:39 GMT, "Shayne Wissler"
wrote in message
TEjBc.149003$Ly.90993@attbi_s01:

Assuming a free market, it would be in a helmet manufacturers best
interest
to be in the business of both, for the same reasons. In the current
mixed-economy it still makes sense for a helmet manufacturer to be
principally concerned with the performance of the helmet and to let
profits
flow from that--it's the only honest way, and it in fact still could lead
to
becoming a market leader.

Why bother when you can use dodgy statistics and emotional blackmail
to coerce the government into mandating the existing, flawed product?

Because it's a whole lot more fun and rewarding to create a great product
and succeed because of its merits than it is to invent schemes for tricking
people into giving you their money.


Shayne Wissler

On Sun, 20 Jun 2004 17:47:32 GMT, "Shayne Wissler"
wrote in message
U4kBc.123595$3x.53424@attbi_s54:

Why bother when you can use dodgy statistics and emotional blackmail
to coerce the government into mandating the existing, flawed product?

Because it's a whole lot more fun and rewarding to create a great product
and succeed because of its merits than it is to invent schemes for tricking
people into giving you their money.

That only works for niche manufacturers like recumbent makers. For
Bell the shareholders don't give a damn about fun, they just want
their money. That's one of the reasons I generally support small
businesses when I have the option - they are much closer to their
customers and much more likely to be motivated by genuine enthusiasm
for the product.

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 Washington University

On Sun, 20 Jun 2004 10:23:42 -0400, Steven Bornfeld
wrote:



John Forrest Tomlinson wrote:
On Sat, 19 Jun 2004 22:31:00 -0400, Steven Bornfeld
wrote:


Mandatory inspection makes a lot more sense to me than
mandatory CPSC regs such as reflectorized pedals.


Who and how many people would this help? In talking about public
policy, you've got to ask what is the benefit and what is the cost? I
see benefit for an extremely small amount of people and cost for an
extremely large number of people. So I don't understand the point of
this suggestion.

JT

I don't know the answer to this. One might think that self-interest
would make automobile inspections unnecessary as well--maybe you agree.
But if you don't, I do not see a fundamental difference in principle.

The difference is that there are huge numbers of people injured in
automoblies and by automobiles every year in the US. Unsafe autos are
a threat not only to the dirivers but to other road users, pedestrians
etc. There is a big cost to society by injuries caused by autos. And
there is also the issue of potential for more pollution by uninspected
autos.

Is there a big problem in the US with accidents to riders of
uninspected bikes? Is there a big problem for other road users caused
by uninspected bikes? I don't think so, but if there is, then what
you suggest makes sense. If not, think of the high costs and low
benefit.

JT

Just zis Guy, you know? wrote:
On Sat, 19 Jun 2004 18:38:51 -0400, Steven Bornfeld
wrote in message
:


Let me see if I get this straight. All the studies showing a benefit
have fatal flaws; all the studies that show no benefit are well-designed.


Not necessarily.

There are, as I said, essentially two sorts of study. Small-scale
prospective studies, of which the 1989 Thompson, Rivara and Thompson
is the best-known; these show unequivocal benefit and large scale
savings in injuries. Then there are population-level studies, which
are equivocal. They show no measurable bnefit. They show lots of
confounding factors.

I have seen rebuttals of all the major pro-helmet papers. Most of
these rebuttals are valid, like the criticism of the control group in
TR&T which effectively makes the whole thing worthless. I have yet to
see any rebuttal of a population-level study. I do read everything I
can find, and I was originally strongly pro-helmet and in favour of
compulsion for children.

One of the key factors in changing my view was the fact that I had no
idea the population level studies even existed. Helmet promoters were
telling me that helmets save 85% of head injuries and 88% of brain
injuries, stated as fact, but then I found that even the original
authors had revised these estimates downwards, and that the figures
were well known to be unreliable. It's like the business of WMD: as
the lies start to be exposed, you have to question whether there is
any basis of truth at all.

Well, this is a different issue. I am concerned with whether the
safety studies are flawed. Intent is not an insignificant issue, but
I'm not really concerned with that for the purposes of this discussion.
Certainly if these studies were funded by the helmet manufacturers it
casts things in a different light.



Actually the real position is probably that helmets prevent most
trivial injuries and very few serious ones. There is a probably
narrow band of cases where helmets may turn a serious injury ionto a
minor injury, but risk compensation also means that there is another
band of cases where the crash would not have happened in the first
place had the rider not been wearing a helmet.


This is something that the anti-helmet partisans continue to repeat,
and I'm not sure what you mean by this. I am inclined to think you're
saying that folks feeling relatively protected will engage in riskier
behavior. I think this is speculative; the same argument the right uses
in this country to attack dispensing of condoms. I've seen plenty of
risky behavior from both helmeted and non-helmeted riders. Of course
this is anecdotal, but I doubt anyone would seriously contend that
people drive more recklessly because they are wearing seat belts.

So overall there are
solid reasons why, at the population level, where only serious and
fatal injuries are counted, there would be no visible effect; while at
the detail level, where all injuries are counted, some effect may be
seen.

All that, I have no problem with.

I do have a problem with helmet promotion which igniores the
distinction between different kinds of crash and different kinds of
injury. The idea that because a helmet saves a cut head it will
necessarily prevent massive brain trauma when hit by a pseeding truck
is laughable, but by using a single figure for injury reductions that
is exactly what the promoters are trying to imply.

I don't doubt that this is done; I personally don't know anyone that
cycles who buys that position though.


I also have a problem with the excessive focus on helmets. In the
minds of the medical and legislative communities, wearing a helmet
seems to be viewed as the first, best thing a cyclist can do to ensure
their safety. There is no credible evidence to support that
prioritisation. The only thing which I can think of which has been
proved everywhere to omprove safety, is more people cycling. So if
you want cycling to be safer, you have to promote cycling (and good
cycling skills, obviously). Promoting helmets requires that you build
the perception of cycling as a hazardous activity, which works against
that goal.


Again, I think that safety measures in general should promote a healthy
respect for the dangers implicit in any given activity. I would view
effective cycling instruction in the same way. For that matter, one
must demonstrate competence before being licensed to drive a motor
vehicle. In spite of this training many drive with a blatant disregard
to the real dangers.
I feel you are almost certainly right about effective cycling
instruction being more important to safety. For that matter, at least
here in the states a very large proportion of those wearing helmets wear
them incorrectly. One wonders how different the population studies
would be were riders fit properly with helmets.
Another issue is cultural; in the UK, and in Europe and most of the
rest of the world, the bicycle is seen as a legitimate means of
transportation. In the U.S. it is overwhelmingly still seen as a toy.
As a consequence of this, very few cyclists--even those who bicycle for
legitimate transportation follow even basic transportation regulations.
(As an aside, while on a bicycle tour I once rode through a red
traffic signal in London--a transgression for which I was vigorously
chastised by several pedestrians. I didn't do it again.) I assume that
the way increased cycling will improve safety is first that there are
less motor vehicles on the road. Furthermore, I would assume that once
cycling reaches a certain critical mass it will have a political
constituency to effect changes in access, motor vehicle regulations etc.
to improve conditions for cyclists. In the U.S. unfortunately this is a
pipe dream. The only thing I see encouraging increased bicycle use is a
severe and sustained shortage of gasoline.



The studies I saw cited are all retrospective studies. I believe it is
possible that somewhere a paper may have been published that confuses
percentages for percentage points. It is hard to believe this happened
multiple times in referreed journals.


There are recognisable flaws with many of the key papers. You can
find some good critiques at http://www.cyclehelmets.org and
http://www.cycle-helmets.com and other places too.


Let me be clear--I am not an expert in safety data nor in epidemiology.
But I am up to my eyeballs in newsgroup pundits (in unrelated fields)
making patently ridiculous claims about the body of evidence in fields
in which I do have expertise. It is impossible for me to evaluate
helmet data for myself, nor have I found it prudent to believe folks
such as yourself who may very well have that expertise.


OK, but some of us are not your garden-variety newsgroup pundits.
Some of those who post have actually done research. I have analysed
UK child hospital admissions returns and found that there is no
significant difference in the proportion of head injuries suffered by
road cyclists and pedestrians, despite helemt wearing rates only
around 15%.

Again, I must ask if this pertains to total number of incidents,
proportion of head injuries among total injuries, head injuries per unit
time, etc. This is a complicated issue; I trust that you have looked at
the design of the studies as apparently some of the journals have not.

That doesn't suggest to me that cycling is especially
dangerous. I work with John Franklin, probably the UK's leading cycle
safety expert, and I've talked to the people who test helemts against
the standards. It was they who told me that modern helmets are far
weaker than those in the TR&T study, and that many helmets fil the
tests anyway.

These guys have shown me that scepticism is not a contrarian view.
That's the point. We are no anti-helemt, we are anti-FUD.

Help me out here--this may be a UK expression--what is FUD? And why
would you not be anti-helmet if the evidence is that they aren't useful
in protecting against serious injury?


Someone is
trying to sell you an expensive product; the manyufacturers can't say
it will save you if you are hit by a car because they know damn well
it won't, so they fund studies and they fund groups like Safe Kids and
they get someone else who won't get sued when you die to tell you that
helmets are a magic panacea to all cycling injuries.


One hopes that people in position of authority choose carefully in whom
they listen to when policy is made.


If only. The UK's Department of Transport currently bases its policy
on an "independent review" written by a team of people all of whom
work together, and several of whom have published papers calling for
helmet compulsion. No sceptic was included in the review body. Some
factual errors have since been removed, but it remains a dogma-driven
document written by those promoting helmets.

There are three sides, you see: pro-helmet, anti-helmet and sceptic.
Most cyclists who have read all the facts become sceptics: they make
up their own minds and think others should also be allowed to do so.
Newbies tend to be pro-helmet, until they realise that their
pro-helmet view is largely the result of not being given all the
facts. The number of anti-helemt people is very small. And I'n not
one of them. See my website if you are in any doubt of that.

That, of course, is a fundamental problem. Any agnostic who argues
with a True Believer will end up sounding like an atheist, even though
they are not.

This of course is true. But unlike religion, this one should be easy
to determine if the will is there.



See, I'm going to have to look up that paper. It is very, very
difficult for me to believe that NEJM would publish a paper with a flaw
that blatant.


Sure. Just as it is hard to believe that the percentage points
problem would have got past the peer review process. But what you
have to remember is that these guys are looking for helmets to work.
When I was training as an engineer i was told to guard against that.
The idea of an experiment is to test a hypothesis, not to find data to
support it. You're supposed to try to disprove, not prove, your
initial premise. In this case the researchers (funded, unless I've
been misinformed, by the Snell Insititue) had already decided on the
outcome before they started.


Well, sure. That's the way it is supposed to be. But drug trials are
not conducted by folks looking for the drugs not to work. Of course,
one cannot do a double-blind study on this. But this is a very serious
charge against the NEJM, and I would have expected to hear about it.


Anyway, if you have trouble getting a copy, let me known and I'll send
you a PDF. I can also give you John Franklin's comments on it.

If you have the study at hand, I'd love to get it (just remove nospam
from my address).



The fact that head injury rates have risen by 40% in the USA in a
period when helmet use rose from 18% to 50% surely tells us something.


Are we talking about cycling head injuries, or total head injuries?


Cycling.


As does the fact that the pro-helmet British government has admitted
that it knows of no case where cyclist safety has improved with
increasing helmet use.


I'd love to hear some context.


It was a letter from the road safety minister to an MP, in response to
a question about whether the Government would be supporting a bill to
compel children to wear cycle helmets, which had been introduced as a
Private Member's Bill. There's a commentary on the process he

url:http://www.chapmancentral.co.uk/web/public.nsf/Documents/martlew_bill

In order to get the Member concerned to move the Bill, the propsers (a
singl;e-issue pressure group) provided a lot of statistics like
"28,000 cycling-related head injuries annually" (which turned out to
be 1,200), and compulsion representing "20,000 tragedies saved every
year" (which turned out to be 500 known serious injuries, almost all
sustained in crashes with motor vehicles).

I return to my earlier point: if the case were that clear-cut, why is
it necessary to exaggerate the figures?

The pressure group also got one grieving mother to travel to London to
promote the Bill, having told her that her child would have lived had
he been forced to wear a helmet (which, of course, you can't prove;
his injury sounds as if it could have been caused by rotational forces
which helmets can't mitigate). So I read the Coroner's report. He
had ridden off the footway into the path of a car because his bike had
defective brakes. Footway riding and riding a bike with defective
brakes are already offences. So why is this a case for comlsory
helemt use, rather than enforcement of existing regulations? And why
should we believe that a teenage boy already breaking two laws would
obey a third? And in any case, telling the mother that if only there
had been a law to compel helmet use her child would be alive today is
a heartless and cynical piece of manipulation.


This was in the UK? This is business as usual in the U.S.



It is certainly understandable to me that racers who'd become
accustomed to the wind in their hair would object to the "intrusion" of
the insurance companies. Certainly there had been no studies back then
demonstrating the uselessness of helmets in preventing serious injuries,
but those I spoke to (some of whom you undoubtedly know personally) were
just as opposed to mandated helmets as you are now.


That was not, in my opinion, an actuarial judgement; there was not
enough data to go on at the time. Quite why a device designed for a
crash at around 12mph should be mandated for racing is an interesting
philosophical question.


Actually in this area you have a point. It was a decision made for the
USCF by whichever insurance carrier was willing to write the liability
policy. Far be it from me to tell you their decisions are made on the
basis of good, rational data. ;-)


Just so. Actuarial data relies on long-term trends and large data
sets. In this case it looks more like a kneejerk reaction to asingle
incident. As those who follow pro racing know only too well, the
mandatory use of helmets has not stopped racing cyclists from dying of
head injuries. The numbers are in any case too small for robust
statistical comparisons to be made.


It was, IIRC, not based upon any one incident. The USOC had lost all
of its liability coverage; the racing season was delayed while another
policy could be found. This one was hammered out de novo.



Only about 10% of cyclist injuries are to the area covered by the
helmet and many (possibly most) cyclists who die of head injury also
have other mortal injuries. Most fatal cyclist injuries are of course
sustained in crashes involving motor vehicles: it is motor traffic,
not cycling, which is dangerous.

Come on! That's a little like saying driving a car isn't
dangerous--it's those darned OTHER drivers who keep crashing into me! ;-)



Statistically you are right of course. But we are talking about
cycling; we might have much more to talk about were this a political or
automotive ng. But I know of several folks who have suffered head
injury, a couple of which were life-threatening (prolonged coma and
permanent neurological damage) without the benefit of motor vehicles.


Sure, but the fact remains that the risk of serious head injury is
(roughly an order of magnitude, according to my figures) higher where
a motor vehicle is involved. Although there is a risk there of
falling into the trap of the compulsion zealots (most of whom seem not
to be cyclists) and bundling all cycling together under a single
heading. That would be like considering a walk in the park and
free-climbing under a single heading. I know one guy who will never
walk again following a bike crash, it was probably caused by wheel
ejection due to his disc brakes. Some people do mad downhilling.
Others ride along traffic-free bike trails. Cycling is a broad
church.

I have crashed my bike and hit my head, and I've crashed and not hit
my head. I know two veterans who had similar crashes, the one wearing
the helmet died and the other survived, both the result of hitting
potholes in the road, no car involved. Life is one giant crapshoot,
after all. In the end, though, the evidence suggests that cycling is
not an unusually dangerous activity.

Well, as you say, there's cycling, and then there's cycling. I made a
decision after a serious crash in my first year racing that I was
finished. It's a bargain you make with yourself--I won't race again and
THEN I'll be safe. I was not spared a head injury by my helmet, but I
probably saved myself having my eyes cut up by the broken glass I fell into.



The biggest problem with helmet promotion is that it reinforces the
perception of cycling as dangeorus without teaching any of the
techniques which reduce the danger. In doing so, it actively deters
cycling, which paradoxically /increases/ risk.


Clarification please: are you talking about relative risk to the rider,
or total risk to the population?


Sound question.

An individual cyclist can reduce the risk to themselves by using good
riding techniques (e.g. Effective Cycling). "Cyclist hit by turnign
goods vehicle" is nasty, often leading to fatal crushing injuries of
the torso. The solutionis simple and obvious: don't ride up the
inside of trucks and buses. If you are going to pass in a traffic
line, do so on the outside, ensure that the driver is not signalling
before you start, be aware that they swing round corners and that the
trailer of a semi cuts in, make sure the driver can see you (if yo
can't see his mirrors, he can't see you). All of which sounds
blindingly obvious, but you'd be amazed at how many cyclists have a
lightbulb moment when you tell them this. There are lots of other
simple techniques and bits of knowledge which help cyclists coexist
more safely with motor traffic. So, the general answer is: for the
individual.

Also, risk to the individual rider is lower where more people cycle.
Cycling also brings health benefits which offset some of the external
risks imposed on the cyclist by motorists, so a regular utility
cyclist will enjoy a lifespan two years or more longer than average
(Mayer Hillman puts the benefits as outweighing the risks by 20:1).


Now, this is likewise the kind of statistic that bothers me. I am
assuming that you are speaking of cardiovascular risk. OK. But the
choice should not be cycling vs. couch potato. I have never seen a
study actually pretend to predict life extension based on a particular
volume of cardiovascular exercise anyway. However, for those who cycle
for fitness instead of purely for transportation (as I do) one cannot
assume that someone who stops cycling will do no other aerobic exercise.
There are other confounding factors, such as that those who bicycle or
do other forms of aerobic exercise are less likely to smoke. I have
seen studies that attempt to correct for this, but they are mostly fantasy.


In terms of the general population, mode switching to cycling has huge
potential benefits. Crashes involving cyclist v cyclist or cyclist v
pedestrian are very rarely fatal or even serious.


My objections to helmet compulsion are not libertarian, but
evidence-based. We have the experience of laws in Australia, New
Zealand and Canada to draw on. In no case did injury rates reduce.
In every case cycling was deterred.


As long as this is not libertarian, and allowing that proper bicycle
maintenance and effective cycling are more important to cyclist safety,
what would your feelings be about:
1) Mandatory licensing of cyclists (as per motor vehicles)
2) Mandatory minimum age for cyclists on public streets and roads
3) Mandatory registration of bicycles and periodic bicycle inspections


All of these have been suggested at various times. They all share one
of the fundamental weaknesses of helmet compulsion, in that they deter
cycling. Almost no restriction is going to affect me, riding 5,000
miles per year or more and with an investment of around $10,000 in
bikes. The rider who has an x-Mart bike and is prompted by a "get off
your ass!" promotion to try riding to the corner shop for his
newspaper will be faced with either going out and getitng a whole load
of expensive training and licenses; breaking the law; or driving
(again). You can guess which is going to win.

There are other reasons, too. For example: most adults already have a
car driver's license. For example: we don't require pedestrians or
horse-riders to be licensed. Licensing is a requirement which applies
to motor vehicles as a response to the extraordinary levels of danger
they impose on others. They have the potential to go very fast, and
they weigh a lot. In an exchange of knietic energy, the final
velocity of pedestrian plus car is indistinguishable form the velocity
of the car beforehand. Massive accelerations cause massive damage.
Bikes are small, light, and relatively slow. So there is not
sufficient concern to justify a licensing scheme. I am absolutely in
favour of voluntary schemes, and schemes run by schools and councils.

Minimum age? Well, where would you put that? My ten-year-old can
ride safely on the roads here, he has already passed Cycling
Proficiency and he's ridden day rides of 50 miles or more with groups.
He doesn't get to ride on some roads because they might require
evasive techniques he's not learned yet, and because they require too
much concentration. His friend of the same age is not allowed on the
road on his own because he has no road sense yet. Most parents should
be smart enough to realise when their child will be safe on the road,
and those who aren't will be placing their child in danger in other
ways too.

Registration and inspection? The deterrent effect, of course, plus
the fact that it would be virtually unenforceable. I would make bike
repairs free fo any local sales taxes, encourage "Dr. Bike" schemes
with free inspections at schools and community centres. I'd even have
beat cops tag bikes which are obviously unsafe. But the danger is
principally to the rider. The danger of a defective car is to those
around the driver.

It's a bit like Russian roulette. With cycling you have five empty
chambers and the gun is pointing at your head. With driving you have
six loaded guns, only one of which is pointed at you, and pull one
trigger at random.


But of course, these are unwelcome messages. When you compare child
head injury rates for road crashes you find that pedestrians and
cyclists have around the same proportion of head injuries, and
pedestrian injuries are much more numerous (the risk levels in
off-road cycling for children are an order of magnitude lower). Any
justification of cycle helmet promotion applies to a much greater
extent to walking helmets. And even more so for car occupants, whose
fatality rate from head injuries is much greater.


Another clarification please: The head injury rates for cyclists vs.
pedestrians vs. auto passengers are for 1) Mile traveled
2)total number in population 3) hour spent in activity


These are the proportions of all admissions which are due to head
injury. So, if you have a bike crash, you are not markedly more
likely to suffer head injury than if you are hit as a pedestrian.

This assumes that the total number of person-hours spent cycling is
roughly equivalent to the total number of person-hours spent as a
pedestrian.


The risk levels comparison: 10% of cycling is on road, 90% off road.


This is a simply amazing statistic. In the U.S. even most mountain
bikes are never ridden off road.


Slightly over 50% of admissions are due to road traffic crashes,
slightly under half due to crashes with no motor vehicle involved.
Allowing for a small number of simple falls in road riding, the risks
are, to a first approximation, an order of magnitude higher for road
riding.


I think that making the auto industry the focus in this discussion in
very much the same way makes it too easy to absolve ourselves of
responsibility in this issue.


The thing is, though, at the moment the entire focus is on us.
Looking at the figures, that's not going to work. Apart from anything
else, the same motor risks affect pedestrians, and the number of
pedestrians killed and injured is very much higher than the number of
cyclists (5-10 times in the UK). Of course motor drivers should not
be the sole focus of attention. But right now they are not the focus
of /any/ attention in the cycle safety debate. That is what needs ot
change.


So what would you change? As you've pointed out, cars are heavily
regulated because of the greater danger. The industry is more powerful
economically and politically. So what would be the focus of improving
bicycle safety vis a vis automobiles?



if we wish to appear to be "doing something",
it is not enough to fault those who think helmet laws will save us; we
must have the courage (and the political clout) to do something that
WILL be meaningful.


Trust me, I am doing far more than bashing the Liddites. My point is,
really, that it is not sufficient for motorists to come along and say
it's all my own fault for not wearing a helmet when they knock me off
my bike. It's been tried by several insurers in the UK, and in each
case thus far they have failed, but that is in part due to work done
by our CTC (largest cycling club) who have set up a Cyclists' Defence
Fund to fight such cases. There is a debate to be had on cycle
safety, and the helemt issue is merely drawing attention away from it.
Actually I'm composing a letter on that issue at present:

url:http://www.chapmancentral.co.uk/web/public.nsf/Documents/IP

Anyway, I can see that you have started to question the orthodox view
on helmets, wich is a good thing. Whether you conclude that you
personally should or should not wear a helemt, I can't say; and
actually I think that's up to you anyway. I think you will probably
come to agree (if you don't already) that helmet compulsion is an
essentially facile solution, an experiment which has failed wherever
it's been tried. It is time to move on to the real issues, as
discussed above.

Guy

Thanks for your interesting and thorough discussion. This is obviously
an important issue for you. The issue of helmet mandates is frankly
unimportant to me. What is important is the truth regarding helmets and
bicycle safety, for myself and my family. As someone who has been
permanently injured in crashes I'm sure it is something on which we both
can agree

Best,
Steve

Frank Krygowski wrote:
Shayne Wissler wrote:

"VC" wrote in message
om...

"Shayne Wissler" wrote in message


news:TQJAc.135474$Ly.96010@attbi_s01...

snip of implication that helmets may increase risk of rotational brain
injury

Not everything is what it seems to be. A helmet may indeed not be so
good for your health.



Nice imagination, but do you have any actual reason to believe that
helmets
increase the rotational forces involved?

Casual observation would imply the opposite. Helmets are more slippery
than
skin...


I doubt that bike helmets are more slippery than skin - or, more
properly, skin covered with a good layer of hair. It's been my guess
that human evolution left hair on the head partly for that reason - to
reduce the effect of a glancing blow (whether in accident or on combat).

When the hair alone can't handle it, the scalp is pretty easily torn,
exposing the well-lubricated scalp layers - a messy but effective second
line of defense.

Scalp injuries can be very risky, esp. if down to the gallea
aponeurotica--there are pretty wide-open venous communications with the
brain.

Steve


No-shell bike helmets were taken off the market when it was claimed they
grabbed the asphalt. The microshells that are now popular don't look
very convincing to me. I'd think they would conform to, and lock to,
asphalt roughness. Perhaps not... but AFAIK, they haven't been tested
for this. Certainly the standards don't address it.

... and they have a larger radius than the skull.


This causes two effects, one probably beneficial, one probably
detrimental. On the good side, the speed of the glancing surface
corresponds to less angular velocity. On the down side, the increased
moment arm means increased torque to cause angular acceleration. Perhaps
the effect is a more rapid acceleration for a shorter period of time -
but again, it hasn't been tested, AFAIK, and it's not addressed in the
standard.

Also, the helmet is not

as tightly coupled to the head as the skin is...


Well, tight straps are demanded by the helmet promoters, and it seems to
me the coupling is enough to induce some serious angular acceleration.
Scalp skin seems (deliberately?) loose. But again: no testing, no
standard.

... and if the helmet got a large
impulse of rotational force from a localized postion on the helmet, it
would
tend to be ripped apart, damping the force.


That could certainly help. I wish there were testing or a standard that
addressed it precisely.

But it's interesting - if this is really what saves a person from
excessive angular acceleration of the brain, then helmet proponents may
need a new song. Instead of "My helmet broke, so it saved my life!!!!"
they may need to say "Thank God my helmet broke, so it didn't kill me!!!"

John Forrest Tomlinson wrote:
On Sun, 20 Jun 2004 10:23:42 -0400, Steven Bornfeld
wrote:



John Forrest Tomlinson wrote:

On Sat, 19 Jun 2004 22:31:00 -0400, Steven Bornfeld
wrote:



Mandatory inspection makes a lot more sense to me than
mandatory CPSC regs such as reflectorized pedals.


Who and how many people would this help? In talking about public
policy, you've got to ask what is the benefit and what is the cost? I
see benefit for an extremely small amount of people and cost for an
extremely large number of people. So I don't understand the point of
this suggestion.

JT

I don't know the answer to this. One might think that self-interest
would make automobile inspections unnecessary as well--maybe you agree.
But if you don't, I do not see a fundamental difference in principle.


The difference is that there are huge numbers of people injured in
automoblies and by automobiles every year in the US. Unsafe autos are
a threat not only to the dirivers but to other road users, pedestrians
etc. There is a big cost to society by injuries caused by autos. And
there is also the issue of potential for more pollution by uninspected
autos.

Is there a big problem in the US with accidents to riders of
uninspected bikes? Is there a big problem for other road users caused
by uninspected bikes? I don't think so, but if there is, then what
you suggest makes sense. If not, think of the high costs and low
benefit.

JT


Protection coming out of the factory is not the responsibility of the
CPSC. Do they do an adequate job? Is the only criterion the amount of
damage the vehicle could do for others?
I don't have the answers--just thinking.

Steve