cycling links

[David Martin]

On 28/11/04 9:30 pm, in article [email protected],
"David Hansen" <[email protected]> wrote:

> On Sun, 28 Nov 2004 21:05:22 +0000 (UTC) someone who may be
> [email protected] (Roberta Hatch) wrote this:-
>
>> The fact of the matter is we are talking about safety on public
>> roads, not some freak accident involving slipping "on a puddle of frozen
>> vomit"
>

The OP was talking about having a friend hit you with an iron bar. Yes,
completely realistic portrayal of my day to day existence, not.

> People slip on vomit on public roads regularly. Whether it is frozen
> or not depends on the temperature.
>
>> or falling down a flight of stairs.
>
> Many people fall down stairs every day, often suffering head
> injuries in the process.
>
> Neither of these things are freak accidents. They are regular and
> predictable.

...d

 

[Just zis Guy, you know?]

On Sun, 28 Nov 2004 20:50:31 +0000 (UTC), [email protected] (Roberta
Hatch) wrote in message <[email protected]>:

>_A case-control study of the
>effectivness of bicycle safety helmets_, RS Thompson, FF Rivara, and
>DC Thompson.

Open goal!

1. The authors assumed as typical the helmet wearing rate from a
relatively homogeneous "control" group comprised of members of a
single HMO, mainly riding as families on bike paths, rather than
contemporaneous street counts. Substituting the latter, published in
another paper co-authored by Rivara, reduces the calculated efficacy
to zero, within the limits of statistical error.

2. The total number of helmeted "cases" and the proportion of
helmeted riders in street counts are too small to provide any robust
statistical inference anyway

3. The study is not randomised, either cases or controls.

4. The study does not distinguish injuries to the scalp from facial
injuries which helmets could not prevent.

5. The "control" group had a completely different crash and injury
profile, and an entirely different demographic; if you believe that
helmets prevented 85% of head injuries in this group then you must
also accept that they prevented 75% of lower limb injuries as well as:
- black skin
- impact with motor vehicles
- poverty
- riding on the streets
- riding alone
- broken legs

6. The study includes not one helmeted cyclist in collision with a
motor vehicle, the major cause of serious and fatal head injuries in
cyclists.

Now, your starter for ten and no conferring: when the helmet wearing
rate in New Zealand went from 43% to over 90% in a single year, why
did the cyclist head injury rate trend the same as it had for the six
years previous and the three years following?

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

 

[James Annan]

Joe Keenan wrote:


> With what scenarios "sans helmet" do I not come up with severe road
> rash on my scalp and side of my face?

Quite probably. Covering your head with a helmet is likely to prevent
minor cuts and grazes. You have to weight that benefit against the
penalty of a larger, heavier head which is more likely to get hit in the
first place. It certainly doesn't sound like much of a case for helmet
compulsion or even advocacy, since the same cut-prevention arguments
apply more strongly to gloves, leggings, knee and elbow protectors. You
could also try a less cumbersome and fragile hat.

James
--
If I have seen further than others, it is
by treading on the toes of giants.
http://www.ne.jp/asahi/julesandjames/home/

 

[Richard]

Jon Senior wrote:
> [1] I have quote-marked "research", as a genuine scientific study would
> reasonably be expected to produce results that match real world
> observations, and to modify their methodology if that was not the case.

<mild pedantry> In my field of science, I'm aware of a modelling paper
that contradicted a particular subset of results from a large number of
observational papers. The modellers were absolutely convinced they
were right and the observations were wrong. The observationalists, of
course, all smirked, but the modellers went through their work with a
fine toothcomb and couldn't find what was wrong. Finally one of them
went to the original data source, and found the standard suite of
processing software from a particular instrument had a bug that had made
all the results for the past 10 years or so wrong by ~50%. So, you see,
sometimes the real world IS wrong and the model is right.

R.

 

[Jon Senior]

Richard [email protected] opined the following...
> Jon Senior wrote:
> > [1] I have quote-marked "research", as a genuine scientific study would
> > reasonably be expected to produce results that match real world
> > observations, and to modify their methodology if that was not the case.
>
> <mild pedantry> In my field of science, I'm aware of a modelling paper
> that contradicted a particular subset of results from a large number of
> observational papers. The modellers were absolutely convinced they
> were right and the observations were wrong. The observationalists, of
> course, all smirked, but the modellers went through their work with a
> fine toothcomb and couldn't find what was wrong. Finally one of them
> went to the original data source, and found the standard suite of
> processing software from a particular instrument had a bug that had made
> all the results for the past 10 years or so wrong by ~50%. So, you see,
> sometimes the real world IS wrong and the model is right.

You pedantry is very mild. Try this.

<pedantry>In the case you cite, the observation of the real world was
wrong.</pedantry>

It is possible that all population level reporting of injury rates are
wrong. In all countries. Using many different methodologies.

But is unlikely. Although worthy of an investigation. Perhaps one could
form the background for a paper which studies the disparity between the
modelled results and the real-world data!

Jon

 

[skip]

"Roberta Hatch" <[email protected]> wrote in message
news:[email protected]...

> Bobbi
>
> ---
> Roberta Hatch '65 Panhead
> Dykes on Bikes, San Francisco, CA (This space for rent)

I remember a segment on TV about a woman who rode with and may have started
a female motorcycle club. Her background seemed unlikely - an ex-investment
banker or something like that. '65 Panhead - Dykes on Bikes - San Francisco
sounds familiar. Could that person have been you or someone you know?

skip

 

[Theo Bekkers]

"Roberta Hatch" wrote
> You people are a barrel of laughs. You sound like motorcyclists
> that make try and make the claim that not only helmets do not help prevent
> injuries, but actually cause them.

A motorcycle helmet is a secondary safety device. They do not prevent
accidents. Carrying 1.5 kg on your head which restricts your hearing and
vision can contribute towards an accident.

They are really effective in preventing unintentional ingestion of Big Green
Bugs. This, and the law, is the reason I wear one.

Theo

 

[DiscoDuck]

Robert Broughton <[email protected]> wrote in message news:<[email protected]>...

> What you will soon learn, Henry, is that when discussion of bicycle helmets
> turns up in newsgroups, it has nothing to do with bicycling, and certainly
> not bicycle safety. This is just about Losertarian philosophy. You'll also
> discover that because Losertarians have such a weak cause, the only way
> they can support it is to tell lies and make things up


Bobby boy, we finally agree. It is terriffic you finally admit your
error and that the helmet law lobby holds a "Losertarian philosophy"
IN addition, you admitting that you were part of a weak cause is a
refreshing bit of honesty on your part. I see you got the therapy you
needed.

You are to be congratulated.

 

[slim]

Tony Raven wrote:
>
> Joe Keenan wrote:
> >
> > One simple personal example of why I believe in wearing a helmet.
> >
> > Short story long:
> >
> > Daughter standing still stradling bike. Not cycling.
> > Age 12.
> > Wearing Helmet.
> > Gets foot tangled.
> > Falls sideways.
> > Force of hitting shoulder on ground forcibly snaps head to right with
> > a large deadening sound of THWACK as helmet strikes pavement.
> > Daughter unconscious.
> > Ambulance to hospital.
> > Diagnosis: Mild Concussion
> >
>
> Does your daughter trip over occassionally when not on the bike? Does
> she hit her head on the ground when she does? Do you make her wear a
> helmet all the time in case she trips over? Do you think having that
> extra half kilo weight strapped to her head had anything to do with why
> her head was forcibly snapped to the right? Yet even in exactly the
> sort of accident it was designed to protect against the helmet failed to
> prevent her being knocked unconcious!

A child does not fall with a horizontal speed 22 mph.

--

http://www.bushflash.com/thanks.html
"Bubba got a BJ, BU$H screwed us all!" - Slim
http://www.worldmessenger.20m.com/weapons.html#wms
George "The AWOL President" Bush: http://www.awolbush.com/
WHY IRAQ?: http://www.angelfire.com/creep/gwbush/remindus.html
http://www.toostupidtobepresident.com/shockwave/chickenhawks.htm

 

[slim]

"Just zis Guy, you know?" wrote:

> You say. But helmets are not designed to protect against motor
> vehicle impacts. Don't stop wearing it, but remember that if you are
> hit by a car you can depend on it to this extent: not at all.

You can say that with absolute metaphysical certainty?

How arrogant!



--

http://www.bushflash.com/thanks.html
"Bubba got a BJ, BU$H screwed us all!" - Slim
http://www.worldmessenger.20m.com/weapons.html#wms
George "The AWOL President" Bush: http://www.awolbush.com/
WHY IRAQ?: http://www.angelfire.com/creep/gwbush/remindus.html
http://www.toostupidtobepresident.com/shockwave/chickenhawks.htm

 

[slim]

Tony Raven wrote:

>
> OTOH a helmet is not all you've got. You have your own care and
> attention. I have found myself being more careful and cautious in
> traffic since I stopped wearing a helmet after reading up all the
> research. I have also found that motorists treat me better curiously.
> Perhaps they see me as more vulnerable with a bare head or maybe my more
> cautious riding gets their sympathy. I am fairly certain that whatever
> the reason it is doing my chances far more good than the helmet ever did.

Please expand on "being more careful and cautious in traffic".

Just how are you doing this?

--

http://www.bushflash.com/thanks.html
"Bubba got a BJ, BU$H screwed us all!" - Slim
http://www.worldmessenger.20m.com/weapons.html#wms
George "The AWOL President" Bush: http://www.awolbush.com/
WHY IRAQ?: http://www.angelfire.com/creep/gwbush/remindus.html
http://www.toostupidtobepresident.com/shockwave/chickenhawks.htm

 

[Tony Raven]

slim wrote:
>
> Tony Raven wrote:
>
>>Joe Keenan wrote:
>>
>>>One simple personal example of why I believe in wearing a helmet.
>>>
>>>Short story long:
>>>
>>>Daughter standing still stradling bike. Not cycling.
>>>Age 12.
>>>Wearing Helmet.
>>>Gets foot tangled.
>>>Falls sideways.
>>>Force of hitting shoulder on ground forcibly snaps head to right with
>>>a large deadening sound of THWACK as helmet strikes pavement.
>>>Daughter unconscious.
>>>Ambulance to hospital.
>>>Diagnosis: Mild Concussion
>>>
>>
>>Does your daughter trip over occassionally when not on the bike? Does
>>she hit her head on the ground when she does? Do you make her wear a
>>helmet all the time in case she trips over? Do you think having that
>>extra half kilo weight strapped to her head had anything to do with why
>>her head was forcibly snapped to the right? Yet even in exactly the
>>sort of accident it was designed to protect against the helmet failed to
>>prevent her being knocked unconcious!
>
>
> A child does not fall with a horizontal speed 22 mph.
>

And helmets are not designed to protect them if they did. They are close
to their limit in a fall from standing still as in the case here. In
the UK more children are hospitalised for head injuries from assaults
than from cycling and per hour they are more likely to get a head injury
from falling or tripping on foot than they are from falling off cycling.
Since low speed accidents are exactly what helmets are designed for
why not start with walking helmets?
http://bmj.bmjjournals.com/cgi/content/full/321/7276/1582

Tony

 

[Tony Raven]

slim wrote:
>
> Please expand on "being more careful and cautious in traffic".
>
> Just how are you doing this?
>

http://www.lesberries.co.uk/ccraft/ccraft.htm
The UK Government published handbook on safe cycling.

Tony

 

[James Annan]

slim wrote:

>
> Tony Raven wrote:
>
>>Joe Keenan wrote:
>>
>>>One simple personal example of why I believe in wearing a helmet.
>>>
>>>Short story long:
>>>
>>>Daughter standing still stradling bike. Not cycling.
>>>Age 12.
>>>Wearing Helmet.
>>>Gets foot tangled.
>>>Falls sideways.
>>>Force of hitting shoulder on ground forcibly snaps head to right with
>>>a large deadening sound of THWACK as helmet strikes pavement.
>>>Daughter unconscious.
>>>Ambulance to hospital.
>>>Diagnosis: Mild Concussion
>>>
>>
>>Does your daughter trip over occassionally when not on the bike? Does
>>she hit her head on the ground when she does? Do you make her wear a
>>helmet all the time in case she trips over? Do you think having that
>>extra half kilo weight strapped to her head had anything to do with why
>>her head was forcibly snapped to the right? Yet even in exactly the
>>sort of accident it was designed to protect against the helmet failed to
>>prevent her being knocked unconcious!
>
>
> A child does not fall with a horizontal speed 22 mph.

Certainly not if she is standing still, as in the above anecdote. Did
you have a point?

James
--
If I have seen further than others, it is
by treading on the toes of giants.
http://www.ne.jp/asahi/julesandjames/home/

 

[Tony Raven]

Roberta Hatch wrote:

>
> Common sense prejudices?! I suggest you take your own advice.
> _Evaluation and Replication of Impact Damage to Bicycle Helmets_, TA
> Smith, D Tees, DR Thom, HH Hurt. _A case-control study of the
> effectivness of bicycle safety helmets_, RS Thompson, FF Rivara, and
> DC Thompson. Then move on over the the Snell Memorial Foundation and
> the CPSC and have a look-see on what they have to say.
>


Yawn. Not the infamous Thompson, Rivara and Thompson old chestnut.
It has just about every error in the book from comparing
non-comparable groups (helmeted children, mostly white, well-off, and
cycling in parks with their parents, with unhelmeted children, mostly
black, cycling in busy urban streets) to statistically inadequate sample
sizes of three. Its the paper which, if analysed using their data and
methodology, predicts a 75% reduction in leg injuries from helmet
wearing (an analysis the authors didn't do by the way). If TRT is the
best you can come up with ......


>
> Wrong. A helemt will help prevent serious injury to the head
> whenever it comes between a head and an object that it shouldn't. It
> you want to dispute than, please do provide a scientific study to back
> up your claim.
>

Try "The efficacy of bicycle helmets against brain injury." Curnow WJ.
Accident Analysis & Prevention, 2003;5 Feb 2003 for starters.
(http://agbu.une.edu.au/~drobinso/AAP2002curnow.pdf)


>
> Your graphs do not prove anything about helmet safety. I sugesst
> you read and learn from those research papers I gave you earlier.
>

You mean you cannot see a single discernable effect on head injury rates
as a result of doubling helmet wearing rates? Doesn't that tell you
anything? As for learning from your research papers, those have been
disected and critiqued a long time ago. Which is why some of us view
anyone who starts by quoting TRT as not having done even the basic
research and analysis.

Tony

 

[Joe Keenan]

"Just zis Guy, you know?" <[email protected]> wrote in message news:<[email protected]>...
> On 28 Nov 2004 11:55:36 -0800, [email protected] (Joe Keenan)
> wrote in message <[email protected]>:
>
> >Yikes. Put razors on your cycling shoes and jump all over me.
>
> I'd slip - those Look cleats are a bugger ;-)

Yup they are. Now you're gonna tell me I shouldn't wear those funny
rubber covers to keep me from slipping!! <g> Sorry Guy, couldn't
resist that one. I know you're gonna counter with: Walk gingerly and
more carefully. Okay, that works!!

>
> >I'm not
> >trying to change your opinion, but your posts are trying to change
> >mine.
>
> A bit. Actually what I want is for you to go and read the source data
> and its published discussions. Having done that you may or may not
> agree with me - I don't mind. The enemy here is widespread public
> ignorance, on which the cynical helmet lobby play. You will not hear
> a helmet company say "this helmet will prevent 85% of injuries"
> because they know damned well it won't. That figure comes from a
> single study with more holes than a Swiss cheese. So the helmet
> manufacturers fund SafeKids to say it for them, and the 85% figure is
> still "out there" and being promoted despite the fact that it is the
> highest figure from any of the major studies, substantially higher
> than the others, and is known to be /completely wrong/. People who
> profess themselves experts, campaigning on the issue, are quoting this
> figure as gospel. They are either ill-informed or liars.
>
> Helmet promoters do this:
>
> - exaggerate the number of injuries
> - conflate genuinely serious injuries with the kinds of knocks and
> bangs we took in our stride twenty years ago
> - exaggerate the risk of death
> - state that helmets prevent nearly all head injuries
> - imply that helmets are as effective against serious injuries as
> minor ones
> - imply that helmets are effective against the kinds of injuries
> people are afraid of, those causing permanent intellectual disablement
> - imply that helmets will be effective against the major source of
> serious injuries, motor traffic.
>
> All these are false.
>
> In the UK the major helmet promoters put out a figure of 50 child head
> injury deaths due to cycling every year. The real figure is ten, out
> of 22 fatalities in total. They said this was an "estimate based on
> under-reporting". I leave it to you to calculate the likelihood of
> 80% of fatal child cyclist head injuries going unreported! The
> official figure for unreported cyclist fatalities is: 0%.

Actually, I have read all of those and more. If I remember right the
85% comes from a study that was done in the 80's. Then again, after
banging my head because I was wearing a helmet, my memory isn't what
it should be. <g> Having read the studies, that's the reason I'm not
saying anything to try and change anyone's opinion. I really don't
know which is "more better".
>
> >I'm saying that I believe it "might"
> >lessen or minimize injury to me. That's all. It works for me.
>
> Might is a good word in this context
>
> >I'd like to hear your counter arguements (and yes..I'm sure willing to
> >listen to the other side) about how not wearing a helmet would have
> >helped me in this one.
>
> >Cycling along at a pretty good clip.
> >Hit a rock which was almost impossible to see. (For this scenario,
> >assume you couldn't see the rock even if you tried, and you really
> >couldn't. Know key lighting? Bright brights? Dark Darks? Was looking
> >at the road because of debris seen earlier, and never saw the
> >"camoflaged" rock. And I was looking at the spot where the rock was.)
> >See it at last minute. Try to avoid it. Don't.
> >Large enough rock to cause an endo.
> >Landed on the side of my head (top right skull portion) and right
> >shoulder.
> >Slid, rubbing the shirt and much skin off my shoulder.
> >The slide also wore away the plastic on the helmet and much of the
> >foam.
> >With what scenarios "sans helmet" do I not come up with severe road
> >rash on my scalp and side of my face?
>
> This one: you are not wearing a helmet so you ride more cautiously and
> miss the rock, or crash much slower.
>
> Actually it is quite possible that any decent hat would prevent
> cranial road-rash (a fact not so much overlooked as walked by
> whistling and looking the other way in the helmet studies).
>
> The most consistent conclusion from helmet studies is that helmeted
> and unhelmeted riders ride differently.
>
> Well done for thinking though The key point is this: prospective
> studies measure the probability of any injury given crash; population
> studies measure the probability of serious injury given ride.
> Population studies consistently show no benefit. So the likely
> explanation is: helmets prevent many trivial injuries, and cause as
> many serious ones as they save.
>
> Oh, and the largest ever prospective study, covering eight million
> crashes in the USA over a 15 year period, found that helmeted cyclists
> were more likely to die.
>
> It is nothing if not confusing.
>
> Check out http://www.cycle-helmets.com/ and
> http://www.cyclehelmets.org to be confused even more
>
> Guy

Yup, been to cyclehelmets.org, but not cycle-helmets.com. I'll go
check it out. As they say in New Yawk: "It couldn't hurt.". And you
can say that wearing or not wearing a helmet!!!

Cheers

Joe

 

[Roberta Hatch]

David Martin <[email protected]> wrote:
>"David Hansen" <[email protected]> wrote:

>> On Sun, 28 Nov 2004 21:05:22 +0000 (UTC) someone who may be
>> [email protected] (Roberta Hatch) wrote this:-

>>> The fact of the matter is we are talking about safety on public
>>> roads, not some freak accident involving slipping "on a puddle of frozen
>>> vomit"

>The OP was talking about having a friend hit you with an iron bar. Yes,
>completely realistic portrayal of my day to day existence, not.

I sugest you actully read what was posted instead of making
up ****. A poster made the claim that his helmet saved his skull
when he hit a curb. Another poster took issue with that. Does, or
does not, a piece of angle iron to the head simulate hitting a curb?

>> Many people fall down stairs every day, often suffering head
>> injuries in the process.

This discussion is about bicycle safety. Now be a good lad
and stay on topic.

Bobbi

---
Roberta Hatch '65 Panhead
Dykes on Bikes, San Francisco, CA (This space for rent)

 

[Roberta Hatch]

Richard <[email protected]> wrote:
>Robert Broughton wrote:

>>>But there is no credible evidence to support the idea that helmets
>>>prevent serious head and brain injuries.

>> Nonsense. There's all sorts of credible evidence. All you have to do is
>> spend some time looking for it.

>As you obviously think that it exists, please provide a reference to a
>whole-population study published in a scientific peer-reviewed journal,
>that shows that bicycle helmets prevent serious head and brain injuries.

Since you seem to be making a claim that helmets do not provide
protection, how about you providing a reference to a whole-population
study published in a scientific peer-reviewed journal, that shows that
bicycle helmets do not prevent serious head and brain injuries.

>Any one will do.

Any one will do.

>No hurry. Don't feel any pressure when you can't find one immediately.

No hurry. Don't feel any pressure when you can't find one immediately.
Bobbi

---
Roberta Hatch '65 Panhead
Dykes on Bikes, San Francisco, CA (This space for rent)

 

[David Martin]

On 29/11/04 2:01 pm, in article [email protected], "Roberta Hatch"
<[email protected]> wrote:

>> The OP was talking about having a friend hit you with an iron bar. Yes,
>> completely realistic portrayal of my day to day existence, not.
>
> I sugest you actully read what was posted instead of making
> up ****. A poster made the claim that his helmet saved his skull
> when he hit a curb. Another poster took issue with that. Does, or
> does not, a piece of angle iron to the head simulate hitting a curb?

The post to which I was replying came up with the specious arguement about
having a friend hit you with an iron bar with or without a helmet. They also
raiseed the 'what if you fell off and your melon hit a kerb'

The 'what if you slipped on a pile of frozen vomit when runnign for a train'
is just as legitimate a hand-wringing exercise for the latter (and did
happen to a friend of mine. I was there at the time and no, he wasn't
wearing a helmet).

The 'get your friend to just miss you with an iron bar' was showing that the
former arguement was specious as it was entirely constructed to prove a
point rather than to reflect a real life scenario.

So, I could go back and reread the thread. You probably missed the point
about securing melons in panniers as well.

...d

 

[Roberta Hatch]

David Hansen <> wrote:
>[email protected] (Roberta Hatch) wrote this:-

>>>We know that, if one uses the
>>>research "method" of one well known paper, cycle helmets prevent a
>>>great percentage of knee injuries. That rather implies that the
>>>"method" is bogus.

>>I'd like a pointer to that paper.

>I suspect you could find a link to this from www.cyclehelmets.org.

Nope. Couldn't find it there. Methinks that since loads
of people seem to have taken that ball and ran with it, and none have
jumped in to provide a pointer to it (including Mr. I have a 160 papers
in my database), it doesn't exist. Probably because someone without
any reading skills, read something into some paper, reported it and now
everyone believes what he said without actually reading the paper.

>>I find it hard to believe that
>>anyone would claim that helmets help prevent knee injuries.

>You miss the point. If the research "method" is valid then it could
>not be applied to data and demonstrate that helmets prevent knee
>injuries. The fact that this can be done rather implies that the
>"method" is bogus and thus tells us nothing about helmets.

I'm not missing any point, because there doesn't seem to be
any paper making the claim you reported. Provide a pointer that
"well known paper" and I'll make a comment.

Bobbi

---
Roberta Hatch '65 Panhead
Dykes on Bikes, San Francisco, CA (This space for rent)