advisor wanted

Just zis Guy, you know? wrote:
On 21 Nov 2005 14:41:07 -0800, said in
.com:


Be sure to get a Snell approved helmet (B90 is the most commonly
available bicycle helmet).


The most commonly available helmet in the US is CPSC certified, not
Snell, and B95 is the current standard.

Many bicycle stores in the U.S. sell Snell certified helmets, in fact I
just purchased one two days ago. B95 is not so common, because it
requires more of a full-face helmet, i.e.
"http://www.dwcanada.com/portfolio/sport-protect/lofox.htm".

The CPSC helmets are more common because it's a lesser standard, easier
to meet and the manufacturer can self-certify.

Specialized are the most common Snell B90 helmets that are available,
though apparently many people have realized this, resulting in
shortages. They are not any more expensive than the CPSC helmets sold in
bicycle shops, the per helmet cost of Snell certification being
negligible. However you're unlikely to find any $15 Snell certified
helmets at the department stores. I paid $30 for a Specialized Chamonix.

Just zis Guy, you know? wrote:

On Tue, 22 Nov 2005 08:50:06 +0000, Peter Clinch
said in :

Remember, that all the experts agree that helmets are very
effective in preventing head injuries in the event of a head impact
crash.

For some values of "head injuries" including the very superficial
ones,

And for values of "all" which excludes the numerous experts who
disagree :-)

Tsk, Buy, how can you possibly disagree with Steven M. Scharf who is, after
all, one of Earth's leading experts in being a self-proclaimed expert..

--
Dave Larrington - http://www.legslarry.beerdrinkers.co.uk/
A *National* Socialist Government did you say, Mr. Chaplin?

Just zis Guy, you know? wrote:
On Tue, 22 Nov 2005 08:50:06 +0000, Peter Clinch
said in :

Remember, that all the experts agree that helmets are very effective in
preventing head injuries in the event of a head impact crash.

For some values of "head injuries" including the very superficial ones,

And for values of "all" which excludes the numerous experts who
disagree :-)

Guy

But Steve's definition of an expert is someone who agrees, so by
definition someone who disagrees is not an expert. Simple really; QED

--
Tony

"The best way I know of to win an argument is to start by being in the
right."
- Lord Hailsham

wrote:

What I know for a fact is that a helmet kept me from making a trip to
an ER for stitches at a minimum. Why can I say that? A pointed rock
PENETRATED the helmet deep enough to scratch my scalp. That helmet is
certainly tougher than my skin. The jury is out on the denisty of my
skull, however. So, figure a $70 helmet versus an ER bill for wound
cleaning and stitching.

Makes economic sense to me.

Most people don't look at the economic aspect. In the U.S., the
deductible for an ER visit is usually $25-50. But it'd be pretty amazing
to find anyone that compares the price of a helmet versus the price of
an ER visit, and makes that the determining factor in deciding whether
or not to wear a helmet.

Overall, the difference in death rates for helmet wearers versus
non-helmet wearers is not order of magnitudes different. The best
studies show the difference is around 3x in terms of fatalities, with
injury rates being about equal. Many of the non-helmeted fatalities
would have been helmeted injuries, so you have to be sure to take things
in context.

In any case, this has diverged from the original post, where the poster
inquired about how to reduce glare by use of a visor. That poster
already understood the relative risks of helmet versus no-helmet, and
was trying to do something about glare.

Once Peter Clinch jumped in with his incorrect statement "there's no
conclusive proof that helmets do anything to reduce your chances of a
serious injury," this turned into another helmet thread.

What is true is that there is no conclusive proof that wearing a helmet
reduces the chance of a head-impact collision, and the number of such
collisions is sufficiently rare that over the whole bicycling population
the statistical difference in death and injuries for helmeted versus
non-helmeted cyclists is insignificant. However there is conclusive
proof that in the event of a head impact accident, a helmet greatly
reduces the severity of injury, and reduces the likelihood that the
injury will turn into a fatality.

SMS wrote:

Overall, the difference in death rates for helmet wearers versus
non-helmet wearers is not order of magnitudes different. The best
studies show the difference is around 3x in terms of fatalities, with
injury rates being about equal.

Where definition of "best" is?

In any case, this has diverged from the original post, where the poster
inquired about how to reduce glare by use of a visor. That poster
already understood the relative risks of helmet versus no-helmet

Actually it would appear not.

Once Peter Clinch jumped in with his incorrect statement "there's no
conclusive proof that helmets do anything to reduce your chances of a
serious injury," this turned into another helmet thread.

But it isn't an incorrect statement.
And since a helmet visor isn't the best way to reduce glare IME, it was
worth pointing out alternatives that do the requested glare reduction
better and don't tangibly change your chances of a serious head injury.

However there is conclusive
proof that in the event of a head impact accident, a helmet greatly
reduces the severity of injury, and reduces the likelihood that the
injury will turn into a fatality.

Not according to the expert witnesses cited near the top of the thread.

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net http://www.dundee.ac.uk/~pjclinch/

Peter Clinch wrote:
SMS wrote:

Overall, the difference in death rates for helmet wearers versus
non-helmet wearers is not order of magnitudes different. The best
studies show the difference is around 3x in terms of fatalities, with
injury rates being about equal.


Where definition of "best" is?

A study that records the fatality and injury rates in accidents occuring
over a long period of time (many years), and includes the presence or
absence of a helmet. This type of study does not get into the question
of the effectiveness of helmet laws, or the likelihood of an accident
occuring in the first place. All it measures is the number of injuries
and their severity, and the number of fatalities, when accidents occur
and are investigated.

Such a study could still be skewed of course. It could be argued that
cyclists that didn't wear helmets were also more likely to be poorer
riders, hence the increase in injuries and fatalities. It could also be
argued that the cyclists that didn't wear helmets actually were better
riders, or risk-compensated, otherwise the difference in injuries and
fatalities would be even greater. Bottom line is that you're not going
to ever get a completely double-blind study, it's not possible. You just
have to go with the best study you can find.

And since a helmet visor isn't the best way to reduce glare IME, it was
worth pointing out alternatives that do the requested glare reduction
better and don't tangibly change your chances of a serious head injury.

The original poster already understood that helmets have been proven to
reduce the likelihood of serious injury, when a crash occurs. Several
people saw this as an opportunity to go into AHZ attack mode.

Not according to the expert witnesses cited near the top of the thread.

I looked back through this thread and did not see any such posts. Who
were you referring to?

SMS wrote:

However there is conclusive
proof that in the event of a head impact accident, a helmet greatly
reduces the severity of injury, and reduces the likelihood that the
injury will turn into a fatality.

Perhaps you could point us to a reference to your "conclusive proof"
because those of us who have read the literature are not aware of any
such research.

--
Tony

"The best way I know of to win an argument is to start by being in the
right."
- Lord Hailsham

Tony Raven wrote:
Sunset Lowracer [TM] Fanatic wrote:

Does hard anodizing cause premature rim cracking due to its brittle
nature, or is rim cracking caused by excessive spoke tension?


I don't know about that but I do know you should always grease the
bottom bracket tapers when fitting the cranks ;-)

Here is photograph illustrating the proper grease pattern for tapirs:
http://zettesworld.com/hdz04b/images/mammals/maltapir14101.jpg.

--
Tom Sherman - Fox River Valley
"Twisting may help if yawl can chew gum and walk." - G. Daniels

Tony Raven wrote:
SMS wrote:


However there is conclusive proof that in the event of a head impact
accident, a helmet greatly reduces the severity of injury, and reduces
the likelihood that the injury will turn into a fatality.


Perhaps you could point us to a reference to your "conclusive proof"
because those of us who have read the literature are not aware of any
such research.


The studies have been posted in every helmet thread. Those that have a
philosophical opposition to helmets simply will not believe them.

SMS wrote:
Tony Raven wrote:
SMS wrote:


However there is conclusive proof that in the event of a head impact
accident, a helmet greatly reduces the severity of injury, and reduces
the likelihood that the injury will turn into a fatality.


Perhaps you could point us to a reference to your "conclusive proof"
because those of us who have read the literature are not aware of any
such research.


The studies have been posted in every helmet thread. Those that have a
philosophical opposition to helmets simply will not believe them.

Which is more dangerous?

Commuting in urban traffic at night with a generator power light
wearing a h*lm*t?

or

Commuting in urban traffic at night with a battery powered HID light
but no h*lm*t?

--
Tom Sherman - Fox River Valley
"Twisting may help if yawl can chew gum and walk." - G. Daniels