published helmet research - not troll

Mitch Haley wrote:

Mark & Steven Bornfeld DDS wrote:

Frank Krygowski wrote:


This latter stuff is what Mayer Hillman was taking into account when he
computed the ratio of years-of-life-gained vs. years-of-life-lost due to
cycling as about 20:1. But I don't know much about how he gathered his
data.


This figure is on the face of it absurd--similar in quality to the
self-serving information purporting to prove helmet efficacy.


Why would you say that?
Let's run some numbers, off the top of my head, and see if Hillman
is at least within an order of magnitude, or if we can dismiss him
as lightly as you do.

Every year, ~800 out of many million cyclists are killed in the USA.
Let's assume the average age to be 25, and they lose 55 years of
life expectancy. 55x800=44,000 man-years lost in America each year.

If I cycle for 50 years, are you willing to allow me an extra 2
years of life expectancy? If so, I'm getting .04 years of life
for every year of cycling. If there are 25 million of me, then
we're saving one million man-years each year, which would imply
a gain/loss ratio of 23 to one.

Either you are using population estimates very far from mine above,
or you are dismissing published research as absurd without even
considering it first.

Mitch.


Are we talking about published research, or numbers "off the top of my
head" and whether I'm "willing to allow an extra 2 years of life
expectency" for your cycling?
Cause if there's a vending machine for 2 extra years, put me in for an
extra large.

Steve

--
Mark & Steven Bornfeld DDS
http://www.dentaltwins.com
Brooklyn, NY
718-258-5001

"Just zis Guy, you know?" writes:

Bill "Evasion" Zaumen. wrote:

And you believe that? You believe that a polystyrene hat is more
effective in preventing severe brain injury than "superficial cuts
and abrasions"? Because that is what they are saying here.

Snipping midsentence as you just did is dishonest.

It would possibly have been, had I been suggesting a different definition of
head injury from the authors' own rather than just saving space, but since I
was working with their definitions, it was emphatically not dishonest.

It *was* dishonest. What I had clearly pointed out was that these
authors used specific definitions of the term "head injury", "brain
injury", and "serious brain injury," and that those definitions are
not what a casual reader might imagine those terms mean.

99% of the people reading these posts will not know the definitions the
authors used without that being part of the discussion. Your snippage
indicates that you have no interest in an honest dicussion of this
issue.


Now address the point: do you accept those authors' assertion that helmets,
uniquely among personal protective equipment, are more effective against the
most serious injuries than against all injuries including trivial ones? It
is a claim also made by TR&T (85% / 88% in their case).

I'd believe that a helmet would not protect you against a chipped
tooth or similar minor injuries to portions of the head not covered by
a helmet. I'd answer the rest, but you'll probably distort the answer
by selective quoting and I don't have time to 'wordsmith' a response
to make that bullet proof.

Grow up, Guy, and stop playing silly games where you misrepresent
what others have said.

In what way did I misrepresent, precisely?

Snipping a post midsentence immediately before the word "but" (which
was surrounded by '*'s or appearing in bold depending on your
newsreader to emphasize it). You obviously cut an important
qualifier, thus distorting the sentence. Can't you at least quote a
full sentence when you respond? That isn't asking a hell of a lot.

--
My real name backwards: nemuaZ lliB

Mitch Haley writes:

"Just zis Guy, you know?" wrote:

In what way did I misrepresent, precisely?

You disagreed with him.
Only liars and frauds disagree with Zaumen and Vandemann.

Mitch.

To quote the vice president of the U.S., Mitch, go f___ yourself.
Guy cut a sentence in have, just before an emphasized "but" and
basically changed the meaning. Then he pretended I had said
something else altogether. That makes him a liar - I have every
reason to suspect that he did it on purpose, not by accident.


--
My real name backwards: nemuaZ lliB

"Just zis Guy, you know?" writes:

Bill Z. wrote:

Like I said: explain how helmets can mitigate rotational forces. On
the one hand they increase the turning moment, and are more likely to
grab the tarmac; on the other, they increase the deceleration time
marginally. So no obvious nett benefit there.

Go read a book on classical mechanics and you might start getting a
clue as to what I'm talking about.

Bill, I have an engineering degree. I understand classical mechanics.

Then I suggest you take a refresher course (and you didn't say what
sort of engineering - for all I know, you design ASICs.) Now, you were
saying???

There is, in short, no evidence that helmets have any effect on
rotational brain injuries. So, where's your evidence to suggest otherwise?
Which papers show effectiveness in this kind of injury? Please give
citations.

Try F=ma, and read "Classical Mechanics" (Herbert Goldstein) cover to
cover for starters. This is a graduate-level text, not the introductory
course most engineers take. If you believe a helmet will mitigate the
peak load at the point it covers, it will reduce any rotational effect
on the brain as well because the torque placed on the brain will be
reduced.

What you are failing to grasp is that the sort of "rotational injury"
you are talking about does *not* require a tangential force along the
surface of the head. An impact normal to the scull will do and is
probably the main contributor. Keep in mind that in general, an impact
normal to the scull does not point towards the center of mass of the
brain, nor the center of mass of the head.

I have been trying not to give you any excuse for your usual evasions in
this subthread, so please provide evidence.

You mean my attempt to get you to behave better is starting to have an
effect? ;-)

--
My real name backwards: nemuaZ lliB

Frank Krygowski writes:

Bill Z. wrote:


Nonetheless, this kind of misinformation and exaggeration is what is
constantly piped out by the "safety industry" and consequently, it's
what everyone "knows." Even though it's demonstrably wrong.

Everyone knows advertising when they see it, and exaggerations are
advertising.

What I wrote was "I don't think anyone seriously claims an 85%
reduction in fatalities, nor in fatal head injuries - that is mostly a
strawman Krygowski et al. like to bring up." A serious claim is
something you'd see in respectable journal, not some brochure or some
random web site.
...

You mean like the infamous Sachs, et al "study" still available on the bhsi
website at http://www.bhsi.org/stats.htm and still cited by true believers
among helmet promoters that took the original TRT "finding" and extrapolated
it to fatalities with the ludicrous assertion that:
You guys claimed that the BHSI is simply a single individual putting
up a
personal web site. Would you mind getting your story straight or at least
consistent? BTW. the title of the page you are complaining about is
"A Compendium of Statistics from Various Sources." That doesn't sound
like the sort of thing anyone should take seriously.

Obviously, Bill, you don't recognize that the Sachs paper referred to
was published in the Journal of the Amercian Medical Association, a
generally "respectable journal."

I was refering to the source you people quoted.


Obviously, you are YET AGAIN arguing about a paper you haven't read!
I'm amazed this sort of thing doesn't embarrass you into silence!

I'm amazed that you have the nerve to lie about what I said, which was
about what he *actually* cited - the BLSI web site - when the text was
sitting their right in front of you. In fact, you guys mentioned the
BHSI as both a major helmet promoter and a one-man operation. What is
it? You can't have it both ways.

The post I replied to was, after all, talking about the use by "helmet
promoters," not Sacks paper (which was only incidentally mentioned)
and the example he brought up was a web site you claimed was the pet
project of someone presumably working out of his garage.

I guess you are trying to stay "on message." And that, Krygowski, is
just one more example of your fundamental dishonesty and sleaziness.

--
My real name backwards: nemuaZ lliB

"Bill Z." wrote in message
...
"Tom Kunich" writes:

"Bill Z." wrote in message
...
Joe Riel writes:


Keep in mind that most materials have an elastic limit. They'll
return to their original shapes if the peak stress is below some
threshold.

Here we go again with Bill and his inability to understand that the foam
in
a helmet compresses very closely to 300 gees across it's entire
compression
distance.

Kunich refuese to admit that the peak force would be higher without
the helmet.

When the peak force WITH a helmet is greater than most bone structures can
stand precisely what difference does it make?

"Mark & Steven Bornfeld DDS" wrote in message
...
I am having great difficulty however finding any well-designed research
demonstrating that cycling improves life expectency in age-matched
populations, adjusting for confounding factors such as diet, cigarette
smoking, etc.

It seems to me that I ran across just such a study one time. The claim was
that it didn't appear to increase life span at all but seemed to provide a
significantly healthier (mental and physical) life span. Of course the
confounding factor here might be that only people that are healthier types
to begin with might be those who desire such exercise.

"Frank Krygowski" wrote in message
...
Bill Z. wrote:
You guys claimed that the BHSI is simply a single individual putting up
a
personal web site. Would you mind getting your story straight or at
least
consistent? BTW. the title of the page you are complaining about is
"A Compendium of Statistics from Various Sources." That doesn't sound
like the sort of thing anyone should take seriously.

Obviously, Bill, you don't recognize that the Sachs paper referred to
was published in the Journal of the Amercian Medical Association, a
generally "respectable journal."

Obviously, you are YET AGAIN arguing about a paper you haven't read!

I'm amazed this sort of thing doesn't embarrass you into silence!

Frank, think about who you're posting to.

"Mitch Haley" wrote in message
...
"Just zis Guy, you know?" wrote:

In what way did I misrepresent, precisely?

You disagreed with him.
Only liars and frauds disagree with Zaumen and Vandemann.

Too true mate.

Tom Kunich wrote:
"Mark & Steven Bornfeld DDS" wrote in message
...

I am having great difficulty however finding any well-designed research
demonstrating that cycling improves life expectency in age-matched
populations, adjusting for confounding factors such as diet, cigarette
smoking, etc.


It seems to me that I ran across just such a study one time. The claim was
that it didn't appear to increase life span at all but seemed to provide a
significantly healthier (mental and physical) life span. Of course the
confounding factor here might be that only people that are healthier types
to begin with might be those who desire such exercise.

I wouldn't hazard a guess one way or another. In fairness, a valid
test would probably be exceedingly difficult to design.
The fact that cycling is reasonably safe and both enjoyable and
utilitarian should be reason enough.
Similarly, in my own field there have been recent studies associating
periodontal disease with cardiovascular and cerebrovascular disease.
Periodontists have conveniently latched onto these studies to claim that
flossing will not only save your teeth, but it may save your life!!!
I'll settle for saving the teeth, and leave the cardiovascular disease
to the cardiologists and thoracic surgeons.

Steve