Austin to Evaluate Local Emergency Room Data to Determine Whetheror Not to Implement an All-Ages Hel

[[email protected]]

Ozark Bicycle wrote:
> [email protected] wrote:
> > ... in my
> > view, if a commercial product can't be correctly used by its typical
> > user, that in itself comes under the heading of "not working."
> >
> > And that reminds me: I recently rode with our area's former chief
> > helmet promoter, the one who had tried to get our club to lobby for a
> > MHL in our state. Even she had her helmet tilted back so far that the
> > top-front of her head was totally exposed. This despite her time spent
> > showing videos in schools, passing out leaflets, etc. about the
> > wondrous properties (and proper use) of helmets.
> >
> > My point is this: if someone as motivated as she can't wear hers
> > properly, it's time to blame the product and its designers, not to use
> > the duped consumers as an excuse.
> >
>
> If you don't handle and cook chicken (for example) properly, you run
> the risk of food poisoning. Shall we blame the purveyors of the
> chicken, or the consumer for the resultant trip to the hospital? After
> all, properly handled and cooked, chicken is not a hazard. Yet,
> salmonellosis is far from rare. Isn't it incumbent upon the
> consumer/user to use the product safely?

The "typical" user of chicken is capable of handling it properly.
Almost all such users do. Salmonella poisoning is relatively rare.

The "typical" user of bike helmets does a much poorer job. The straps
are not easy to adjust; once adjusted, they don't retain adjustment
very well; and helmets are often somewhat uncomfortable if properly
adjusted. (Rules like "you should not be able to get more than two
fingers between your chin strap and your chin" or "Your straps should
make it hard to open your mouth wide" come to mind.)

Even among enthusiasts, it's easy to spot bike helmets sitting crooked,
tilted back, straps overly loose, etc. These badly fitting helmets are
common, not rare. It's a sign of a badly designed product.

- Frank Krygowski

 

[[email protected]]

SMS wrote:
>
> . If you
> take the injury data out of context, and ignore the fatality data, you'd
> say that helmets have no effect. When you include the fatality data, you
> see just how well helmets work.


The fatality data I'm familiar with - either fatality trends over time,
or differences in fatalities when MHLs suddely raise the percentage of
cyclists in helmets - show no helmet benefit.

Note that cycling fatalities, while still very rare, rose 20% last
year, according to NHTSA. Does that mean that bike helmet use suddenly
dropped?

No, of course not. Helmets are not designed to protect against
fatalities. They can't.

- Frank Krygowski

 

[Ozark Bicycle]

[email protected] wrote:
> Ozark Bicycle wrote:
> > [email protected] wrote:
> > > ... in my
> > > view, if a commercial product can't be correctly used by its typical
> > > user, that in itself comes under the heading of "not working."
> > >
> > > And that reminds me: I recently rode with our area's former chief
> > > helmet promoter, the one who had tried to get our club to lobby for a
> > > MHL in our state. Even she had her helmet tilted back so far that the
> > > top-front of her head was totally exposed. This despite her time spent
> > > showing videos in schools, passing out leaflets, etc. about the
> > > wondrous properties (and proper use) of helmets.
> > >
> > > My point is this: if someone as motivated as she can't wear hers
> > > properly, it's time to blame the product and its designers, not to use
> > > the duped consumers as an excuse.
> > >
> >
> > If you don't handle and cook chicken (for example) properly, you run
> > the risk of food poisoning. Shall we blame the purveyors of the
> > chicken, or the consumer for the resultant trip to the hospital? After
> > all, properly handled and cooked, chicken is not a hazard. Yet,
> > salmonellosis is far from rare. Isn't it incumbent upon the
> > consumer/user to use the product safely?
>
> The "typical" user of chicken is capable of handling it properly.

And the "typical' cyclist is capable of properly adjusting a helmet.

> Almost all such users do. Salmonella poisoning is relatively rare.
>

But not rare, in absolute numbers.


> The "typical" user of bike helmets does a much poorer job.

Because most are never shown how (or why) to do it.

> The straps
> are not easy to adjust;

OSAF (Opinion Stated As Fact).

> once adjusted, they don't retain adjustment
> very well;

Bollocks. My helmet straps only need readjustment if there is a change
in weather and, hence, my other headgear (sweatband v. earcover, for
example) changes. This is over a period of sixteen years with five
different helmets from two distinctly different makers.


>and helmets are often somewhat uncomfortable if properly
> adjusted.

*More* OSAF.

> (Rules like "you should not be able to get more than two
> fingers between your chin strap and your chin" or "Your straps should
> make it hard to open your mouth wide" come to mind.)
>

Do you often "open your mouth wide" whilst riding? Trying to catch bugs
as a protein supplement?


> Even among enthusiasts, it's easy to spot bike helmets sitting crooked,
> tilted back, straps overly loose, etc. These badly fitting helmets are
> common, not rare. It's a sign of a badly designed product.
>

IME, if I take a few minutes showing someone how (and why) a helmet
should be adjusted, they tend to wear their helmets properly in the
future (over a period of years).

It really is a simple matter of education. I see a surprising number of
people with poorly positioned and adjusted seatbelts, as well. That's
an education issue, too.

> - Frank Krygowski

 

[[email protected]]

Ozark Bicycle wrote:
>
> IME, if I take a few minutes showing someone how (and why) a helmet
> should be adjusted, they tend to wear their helmets properly in the
> future (over a period of years).
>
> It really is a simple matter of education...

And yet, the main mandatory helmet proponent in our metro area, the one
who had gone into countless schools to teach about helmet use, the one
who passed out hundreds of pamphlets, did not have her own helmet
remotely correct.

She's no dummy, Ozark. She's back in school for yet another advanced
degree, after many successful years in jobs much more complicated than
yours.

One thing to be cautious about is overestimating the "average" skill
set, especially when one's own is above average. I've had guys with
PhDs in Electrical Engineering come to me, deparate for help adjusting
their bike's brakes. Very intelligent guys - but not mechanical.

You probably have better than average mechanical skills, so fiddling
with straps, buckles and tensions probably comes easier to you than to
most.

FWIW, I've got a nice collection of helmet photos taken from various
publications, with helmets (most commonly) tilted back like yarmulkes,
or tilted to one side, or in one case, worn backwards!

- Frank Krygowski

 

[[email protected]]

gds wrote:
> [email protected] wrote:
> > gds wrote:
> > > 2)You are also confusing real world ER visit behaviour with whatever
> > > you think it might be. Most studies I've seen report just the opposite
> > > of what you are suggesting. That is the poor and uninsured use ER's and
> > > the wealthier and insured use other modes of getting care.
> > > Of course, if the injury is really severe that doesn't apply and the
> > > ambulance goes to the ER.But since you posit that there are virtually
> > > no serious injuries from cycling that shouldn't mean much.
> >
> > I'd like a citation on the "most studies" parrt of that.
>
>
> Google Emergency room visits and insurance status and you will find
> tons of them!
> Most of the studies find that uninsured have higher ER utilization
> rates than insured. In the studies that did not find this relationship
> they found that the high utilizers were the "publicly insured" that is
> medicaid and medicare. If you want to argue that the medicaid and
> medicare populations using ER's for health care have the same socio
> economic status as privately insured go right ahead, but I don't
> believe that to be the case.

Here's what would be a pertinent citation: The results of a study
correlating average severity of injury presenting to ER, versus
insurance status or income level. My contention is that when a minor
injury occurs, a low-income or uninsured person would be more likely to
treat it at home than a well-insured person.

For example,
http://www.pnhp.org/news/2005/july/immigrants_health_c.php says
"Immigrant children visit emergency rooms significantly less than
non-immigrant children, but their individual ER costs are nearly three
times higher ($45 vs. $18 per capita), suggesting that immigrant
children forego needed care until experiencing an emergency." Of
course, I'm using "immigrant" as a proxy for "low income," and that's
not necessrily a perfect assumption. But have you seen data to the
contrary?

ISTM that even if it comes down to simple transportation problems -
driving to the hospital in the Lexus, versus taking the bus - lower
income folks will face obstacles that will dissuade them from "casual"
ER visits. They'll go to ER only if they think they really need to.
(The issue of going to ER instead of going to a doctor is beside the
point; the point is, what level of injury will trigger a visit?)

And remember, that original 1989 study by Thompson & Rivara definitely
showed significant differences in accident and injury characteristics
of the helmeted and non-helmeted group. The non-helmeted group did
have more severe crashes, and worse "other" injuries. It seems silly
to pretend that the helmets were the _only_ pertinent factor!


> Again you are not reading what I write. An ER doc does NOT need to
> understand how a helmet works in order to make the statement " patients
> who reported wearing a helmet had less severe injuries than those
> reporting not waring a helmet." Such a statement does not explain
> anything causal but mearely suggest a relationship (correlation).

It can certainly suggest a correlation. But ISTM the people
constructing this "study" are not prepared to interpret it as anything
_but_ causation. Do you disagree?

>
> Don't you think it would be interesting and important to see what a
> whole bunch of folks that actually see and treat such injuries observe?
> I do! Let's not get caught up in the specifics of this study and any
> bias it may have. If it is biased it is no good--no argument. But the
> idea of knowing the observations of lots of folks who treat trauma on a
> regular basis is clearly an important bit of knowledge.

Again, I'd think it would be a _little_ interesting to see, _if_ I knew
their observations were done without bias. But I can tell you for sure
that the ER guys and head injury conselors I've talked to have
absolutely no idea of the design standards for helmets. Also, they've
not bothered to notice the relative rarity of serious bike head
injuries. IOW, they've bought the propaganda that helmets are
wonderfully protective, and absolutely needed.

It also seems hard to ignore the implied "We'll show 'em!" attitude of
those associated with this proposed study. It certainly seems like
their conclusions are already written; they just need some data to
wave.

One of my colleagues made a good living as an expert witness in court
cases, doing things like deceleration calculations, collision speed
estimates, etc. What he knew about were things like impact forces,
kinetic energy, collision mechanics, etc. which came through his PhD in
Mechanical Engineering.

Asking a surgeon, for example, to question his judgement would be just
silly. My colleague would know enough not to attempt brain surgery. A
brain surgeon (or other ER doctor) should know enough not to attempt
accident reconstruction.

- Frank Krygowski

 

[Ozark Bicycle]

[email protected] wrote:
> Ozark Bicycle wrote:
> >
> > IME, if I take a few minutes showing someone how (and why) a helmet
> > should be adjusted, they tend to wear their helmets properly in the
> > future (over a period of years).
> >
> > It really is a simple matter of education...
>
> And yet, the main mandatory helmet proponent in our metro area, the one
> who had gone into countless schools to teach about helmet use, the one
> who passed out hundreds of pamphlets, did not have her own helmet
> remotely correct.
>

Yet there is no evidence that anyone ever showed her how (and why) to
properly adjust a helmet.


> She's no dummy, Ozark. She's back in school for yet another advanced
> degree,

Not at all relevant.


> after many successful years in jobs much more complicated than
> yours.
>

I'm going to let that cheap shot pass.


> One thing to be cautious about is overestimating the "average" skill
> set, especially when one's own is above average. I've had guys with
> PhDs in Electrical Engineering come to me, deparate for help adjusting
> their bike's brakes. Very intelligent guys - but not mechanical.
>
> You probably have better than average mechanical skills, so fiddling
> with straps, buckles and tensions probably comes easier to you than to
> most.
>
> FWIW, I've got a nice collection of helmet photos taken from various
> publications, with helmets (most commonly) tilted back like yarmulkes,
> or tilted to one side, or in one case, worn backwards!
>

And this is a simple matter of education and instruction. Fault the
helmet makers and, especially, the LBSs for allowing this state of
affairs to exist, for not doing a better job of educating the consumer.
That said, it has nothing to do with the efficacy of helmets; if no one
shows you how to lace, tighten and tie a shoe, you might get blisters,
or even trip and fall. That is not an inherent flaw in the design of
the shoe.

 

[Smokey]

Ozark Bicycle wrote:
> [email protected] wrote:
> > Ozark Bicycle wrote:
> > >
> > > IME, if I take a few minutes showing someone how (and why) a helmet
> > > should be adjusted, they tend to wear their helmets properly in the
> > > future (over a period of years).
> > >
> > > It really is a simple matter of education...
> >
> > And yet, the main mandatory helmet proponent in our metro area, the one
> > who had gone into countless schools to teach about helmet use, the one
> > who passed out hundreds of pamphlets, did not have her own helmet
> > remotely correct.
> >
>
> Yet there is no evidence that anyone ever showed her how (and why) to
> properly adjust a helmet.
>
>
> > She's no dummy, Ozark. She's back in school for yet another advanced
> > degree,
>
> Not at all relevant.
>
>
> > after many successful years in jobs much more complicated than
> > yours.
> >
>
> I'm going to let that cheap shot pass.
>
>
> > One thing to be cautious about is overestimating the "average" skill
> > set, especially when one's own is above average. I've had guys with
> > PhDs in Electrical Engineering come to me, deparate for help adjusting
> > their bike's brakes. Very intelligent guys - but not mechanical.
> >
> > You probably have better than average mechanical skills, so fiddling
> > with straps, buckles and tensions probably comes easier to you than to
> > most.
> >
> > FWIW, I've got a nice collection of helmet photos taken from various
> > publications, with helmets (most commonly) tilted back like yarmulkes,
> > or tilted to one side, or in one case, worn backwards!
> >
>
> And this is a simple matter of education and instruction. Fault the
> helmet makers and, especially, the LBSs for allowing this state of
> affairs to exist, for not doing a better job of educating the consumer.
> That said, it has nothing to do with the efficacy of helmets; if no one
> shows you how to lace, tighten and tie a shoe, you might get blisters,
> or even trip and fall. That is not an inherent flaw in the design of
> the shoe.

I just bought a new Giro Eclipse helmet and it had an owner's booklet
with a very thorough explanation of how to adjust the helmet and
strongly advised against things like wearing it too high on the head or
with an incorrectly adjusted strap. The adjustments were very easy to
make and once done it was very comfortable on my head. The one I had
before it was a six year old Trek that also had a good owner's booklet
with it. It was not as comfortable or as light as this one and I was
surprised at how far helmet design had come in the last few years.

For the record, I am strongly against mandatory helmet laws.

Smokey

Smokey

 

[Lo]

SMS wrote:
> Lo wrote:
>
> > "The earliest murmurings that I heard against helmets were from a
> > neurosurgeon who I worked for in 1994. He claimed that cycle helmets
> > were turning what would have been focal head injuries, perhaps with an
> > associated skull fracture, into much more debilitating global head
> > injuries. We had a couple of examples on the ward at the time, and it
> > was a bit worrying. However, I wasn't too convinced as I figured that
> > the injuries that would previously have been focal head injuries may
> > well have been resulting in death, so the neurosurgeon was never
> > actually seeing them. Instead, they were making their way straight to
> > the pathologist."
>
> Yes, that's the logical conclusion from the FARS data as well. If you
> take the injury data out of context, and ignore the fatality data, you'd
> say that helmets have no effect. When you include the fatality data, you
> see just how well helmets work.

Eh? I thought the FARS data for helmet use was incorrect. The form
states: Restraint System Use, with Code "00" meaning "None
Used--Vehicle Occupant; Not Applicable". Apparently some FARS coders
checked 00 for not applicable, not realising that, for cyclists,
helmets were defined as a restraint system and that 00 was the code for
cyclists not wearing helmets.

According to FARS, only 3.4% of cyclists fatally injured in California
from 1994-98 wore a helmet, compared to 13.2% according to California's
StateWide Integrated Traffic Records System (SWITRS). Assuming SWITRS
is correct, the FARS data for cycle helmet wearing are useless.

The SWITRS data indicate that helmets prevent few, if any, fatalities.
As do data from other countries - like the Australian data showing that
80% of fatally injured cyclists wore helmets, no different to
population wearing rates.

So, if correctly-recorded fatality data (as opposed to FARS) show no
benefit of helmets, and in the experience of a neurosurgeon treating
head injuries, cycle helmets were turning what would have been focal
head injuries, perhaps with an associated skull fracture, into much
more debilitating global head injuries, what real evidence is there of
benefit?

Lo

 

[[email protected]]

Smokey wrote:
>
> I just bought a new Giro Eclipse helmet and it had an owner's booklet
> with a very thorough explanation of how to adjust the helmet and
> strongly advised against things like wearing it too high on the head or
> with an incorrectly adjusted strap. The adjustments were very easy to
> make and once done it was very comfortable on my head.

I'll be curious as to how long it stays in adjustment. ISTM that it's
common for straps to either creep or stretch out of adjustment, even
when initially done correctly.

Out of curiosity, how were the strap adjustments made on your helmet?

Within the past year, I've been asked by three people to help them
adjust their helmets (or their kid's). I'm sorry I don't remember the
brands, but two had straps that had to be fought to slide through
ordinary plastic buckles, because they had crept out of adjustment.
The third had flattish, round twist locks built into the side buckle,
but they were difficult for the owner to operate. She wasn't sure when
they were locked or not.

None had locks on the buckle controlling the length of the chin strap,
IIRC (although at least one had a sort of rubber O-ring). All were
very badly adjusted when I started working on them. At least one was
still not exactly right at the finish, because the owner said "Oh,
that's good enough" despite temple straps that were obviously loose.

- Frank Krygowski

 

[Cathy Kearns]

<[email protected]> wrote in message
news:[email protected]...
>
> And that reminds me: I recently rode with our area's former chief
> helmet promoter, the one who had tried to get our club to lobby for a
> MHL in our state. Even she had her helmet tilted back so far that the
> top-front of her head was totally exposed. This despite her time spent
> showing videos in schools, passing out leaflets, etc. about the
> wondrous properties (and proper use) of helmets.
>
> My point is this: if someone as motivated as she can't wear hers
> properly, it's time to blame the product and its designers, not to use
> the duped consumers as an excuse.

The mom I was thinking of in my example always wears her helmet like that,
on the back of her head, tilting up behind her hairline. I can't believe
she could hold her head up straight without the back of her helmet bumping
her in the neck. She also rides down the wrong side of the street, with her
children, and then steers them into the "out" of the school parking lot.
Meanwhile yelling at people like me that I should be wearing a helmet.
She's a pediatrician. Her husband is an ER doctor.

 

[Bill Sornson]

[email protected] wrote:
> Smokey wrote:
>>
>> I just bought a new Giro Eclipse helmet and it had an owner's booklet
>> with a very thorough explanation of how to adjust the helmet and
>> strongly advised against things like wearing it too high on the head
>> or with an incorrectly adjusted strap. The adjustments were very
>> easy to make and once done it was very comfortable on my head.

> I'll be curious as to how long it stays in adjustment. ISTM that it's
> common for straps to either creep or stretch out of adjustment, even
> when initially done correctly.

Mine don't.

> Out of curiosity, how were the strap adjustments made on your helmet?
>
> Within the past year, I've been asked by three people to help them
> adjust their helmets (or their kid's). I'm sorry I don't remember the
> brands, but two had straps that had to be fought to slide through
> ordinary plastic buckles, because they had crept out of adjustment.
> The third had flattish, round twist locks built into the side buckle,
> but they were difficult for the owner to operate. She wasn't sure
> when they were locked or not.
>
> None had locks on the buckle controlling the length of the chin strap,
> IIRC (although at least one had a sort of rubber O-ring). All were
> very badly adjusted when I started working on them. At least one was
> still not exactly right at the finish, because the owner said "Oh,
> that's good enough" despite temple straps that were obviously loose.
>
> - Frank Krygowski

For someone so devoted to "hard science", you sure seem to rely on anecdotes
a lot: Happen to see some well-known pro-lid woman with her helmet pushed
back. Random people seeking you out to help them with their
oh-so-complicated brain bucket devices. Etc. Either you're just making up
stories, OR (assuming you're honest) it's second-hand fluff anyway. (You
know, the type of stuff you dismiss derisively when PRO-lid people offer
similar tales.)

HTH (but doubt it), BS

 

[Ozark Bicycle]

Bill Sornson wrote:
> [email protected] wrote:
> > Smokey wrote:
> >>
> >> I just bought a new Giro Eclipse helmet and it had an owner's booklet
> >> with a very thorough explanation of how to adjust the helmet and
> >> strongly advised against things like wearing it too high on the head
> >> or with an incorrectly adjusted strap. The adjustments were very
> >> easy to make and once done it was very comfortable on my head.
>
> > I'll be curious as to how long it stays in adjustment. ISTM that it's
> > common for straps to either creep or stretch out of adjustment, even
> > when initially done correctly.
>
> Mine don't.
>

Neither do mine. And that experience spans sixteen years and five
different helmets from two distinctly different makers.

Just recently, I helped someone adjust a helmet purchased for less than
$20 at Wal-Mart. It was not as simple as with some more expensive
helmets, but it *still* took less than 10 minutes.

> > Out of curiosity, how were the strap adjustments made on your helmet?
> >
> > Within the past year, I've been asked by three people to help them
> > adjust their helmets (or their kid's). I'm sorry I don't remember the
> > brands, but two had straps that had to be fought to slide through
> > ordinary plastic buckles, because they had crept out of adjustment.
> > The third had flattish, round twist locks built into the side buckle,
> > but they were difficult for the owner to operate. She wasn't sure
> > when they were locked or not.
> >
> > None had locks on the buckle controlling the length of the chin strap,
> > IIRC (although at least one had a sort of rubber O-ring). All were
> > very badly adjusted when I started working on them. At least one was
> > still not exactly right at the finish, because the owner said "Oh,
> > that's good enough" despite temple straps that were obviously loose.
> >
> > - Frank Krygowski
>
> For someone so devoted to "hard science", you sure seem to rely on anecdotes
> a lot: Happen to see some well-known pro-lid woman with her helmet pushed
> back. Random people seeking you out to help them with their
> oh-so-complicated brain bucket devices. Etc. Either you're just making up
> stories, OR (assuming you're honest) it's second-hand fluff anyway. (You
> know, the type of stuff you dismiss derisively when PRO-lid people offer
> similar tales.)
>
> HTH (but doubt it), BS

 

[gds]

[email protected] wrote:
> gds wrote:
> > [email protected] wrote:
> > > gds wrote:
> > > > 2)You are also confusing real world ER visit behaviour with whatever
> > > > you think it might be. Most studies I've seen report just the opposite
> > > > of what you are suggesting. That is the poor and uninsured use ER's and
> > > > the wealthier and insured use other modes of getting care.
> > > > Of course, if the injury is really severe that doesn't apply and the
> > > > ambulance goes to the ER.But since you posit that there are virtually
> > > > no serious injuries from cycling that shouldn't mean much.
> > >
> > > I'd like a citation on the "most studies" parrt of that.
> >
> >
> > Google Emergency room visits and insurance status and you will find
> > tons of them!
> > Most of the studies find that uninsured have higher ER utilization
> > rates than insured. In the studies that did not find this relationship
> > they found that the high utilizers were the "publicly insured" that is
> > medicaid and medicare. If you want to argue that the medicaid and
> > medicare populations using ER's for health care have the same socio
> > economic status as privately insured go right ahead, but I don't
> > believe that to be the case.
>
> Here's what would be a pertinent citation: The results of a study
> correlating average severity of injury presenting to ER, versus
> insurance status or income level. My contention is that when a minor
> injury occurs, a low-income or uninsured person would be more likely to
> treat it at home than a well-insured person.
>
> For example,
> http://www.pnhp.org/news/2005/july/immigrants_health_c.php says
> "Immigrant children visit emergency rooms significantly less than
> non-immigrant children, but their individual ER costs are nearly three
> times higher ($45 vs. $18 per capita), suggesting that immigrant
> children forego needed care until experiencing an emergency." Of
> course, I'm using "immigrant" as a proxy for "low income," and that's
> not necessrily a perfect assumption. But have you seen data to the
> contrary?
>
> ISTM that even if it comes down to simple transportation problems -
> driving to the hospital in the Lexus, versus taking the bus - lower
> income folks will face obstacles that will dissuade them from "casual"
> ER visits. They'll go to ER only if they think they really need to.
> (The issue of going to ER instead of going to a doctor is beside the
> point; the point is, what level of injury will trigger a visit?)
>
> And remember, that original 1989 study by Thompson & Rivara definitely
> showed significant differences in accident and injury characteristics
> of the helmeted and non-helmeted group. The non-helmeted group did
> have more severe crashes, and worse "other" injuries. It seems silly
> to pretend that the helmets were the _only_ pertinent factor!
>
>
> > Again you are not reading what I write. An ER doc does NOT need to
> > understand how a helmet works in order to make the statement " patients
> > who reported wearing a helmet had less severe injuries than those
> > reporting not waring a helmet." Such a statement does not explain
> > anything causal but mearely suggest a relationship (correlation).
>
> It can certainly suggest a correlation. But ISTM the people
> constructing this "study" are not prepared to interpret it as anything
> _but_ causation. Do you disagree?
>
> >
> > Don't you think it would be interesting and important to see what a
> > whole bunch of folks that actually see and treat such injuries observe?
> > I do! Let's not get caught up in the specifics of this study and any
> > bias it may have. If it is biased it is no good--no argument. But the
> > idea of knowing the observations of lots of folks who treat trauma on a
> > regular basis is clearly an important bit of knowledge.
>
> Again, I'd think it would be a _little_ interesting to see, _if_ I knew
> their observations were done without bias. But I can tell you for sure
> that the ER guys and head injury conselors I've talked to have
> absolutely no idea of the design standards for helmets. Also, they've
> not bothered to notice the relative rarity of serious bike head
> injuries. IOW, they've bought the propaganda that helmets are
> wonderfully protective, and absolutely needed.
>
> It also seems hard to ignore the implied "We'll show 'em!" attitude of
> those associated with this proposed study. It certainly seems like
> their conclusions are already written; they just need some data to
> wave.
>
> One of my colleagues made a good living as an expert witness in court
> cases, doing things like deceleration calculations, collision speed
> estimates, etc. What he knew about were things like impact forces,
> kinetic energy, collision mechanics, etc. which came through his PhD in
> Mechanical Engineering.
>
> Asking a surgeon, for example, to question his judgement would be just
> silly. My colleague would know enough not to attempt brain surgery. A
> brain surgeon (or other ER doctor) should know enough not to attempt
> accident reconstruction.
>
> - Frank Krygowski

With regard to income level and ER utilization. There is a whole host
of studies that show the relationship to be inverse. You can google up
hundreds of them. You are imagining the wrong choice. It is not ER vs.
home treatment (essentially no treatment). Except for very serious
trauma it is ER vs. private medical care. When I have a minor injury I
go to my docs office. Of course, if I was seriously injured I would be
taken to an ER. But there are myriad studies showing that lower income
groups use the ER for true emergencies and for primary care as they
don't have a relationship with a primary care doc. So, this is not only
a waste of resources as ER's are much higher cost providers than a
docs office; but it also skew that data since many of the less serious
injuries among the wealthier and better insured do not show up in ER
statistics because w don't go there for that type of care. I'm not even
going to argue this further because the number of studies that have
shown this for the past 40 years are enormous.

And why beat the dead horse of bias? No one is arguing that if a study
is biased it isn't worth much. So constantly repeating that mantra
accomplishes what?
However, it is not always correct to assume that because one expects
are certain outcome they will be biased. Bias is only if they either
design the study so that that outcome must be obtained or if they twist
the interpretation of the data to achieve that result. having
expectations is normal.
On that subject there is a very good example in another field. David
Swensen, who is arguabley the best manager of university endowment
funds n the US, set out to write an investment how to book so that the
"average" investor could invest like he did. However, after doing the
research needed to write the book he concluded that it was impossible.
He concluded that without the huge amount of capital and with that
access to very select investment vehicles and advice it was impossible.
So, instead he concluded that the average individual was best off just
buying index funds. Nothing to do with helmets but it does address the
point that for a honest researcher it is perfectly OK to have outcome
expectaions as long as they don't drive your conclusions.

 

[[email protected]]

Ozark Bicycle wrote:
> Frank, recently you have ceased claiming that "helmets make cycling
> more dangerous",

Those are quotation marks - but I don't recall those being my words.
Citation?

> that "helmets make it more likely you will hit your
> head",

?? I think it's obvious that helmets will make it more likely you will
hit your head. I haven't ceased claiming that at all.

> that helmet use causes "risk compensation" etc., etc.

Nor do I doubt they cause risk compensation. ISTM you are
misinterpreting or mis-remembering much.

> But now, you are clutching at the straw that they are hard
> to adjust properly and frequently go out of adjustment, etc. It's a
> song you seem to be singing alone.

>From a helmet promotion website:
"Strap creep affects the basic protection of your helmet. When the
strap loosens, the helmet can slip back, exposing your forehead, or
forward, exposing the back of your head. You can actually hit on your
bare forehead while still wearing your helmet! And if your helmet is
one of the elongated models, a loose strap lets that rear tail push the
helmet out of postion...

"Now where is that perfect helmet that doesn't require all this
fiddling and extra stuff?"

> If you can't properly adjust a
> helmet, see if you can find someone who can show you how to do it
> properly; there's no shame in needing instruction.

Reading comprehension, Ozark, reading comprehension!

I _can_ adjust helmets. I do so when asked by others - and they know
to ask me. Believe it or not, I have a reputation for knowing such
things. That reputation comes partly, but not entirely, because I'm
nationally certified to teach such things. IOW, I'm one of the guys
that _gives_ the instruction.

But the typical consumer is not good at adjusting helmets. While I can
probably dig out the complete citation of the original paper, I'll give
this quote instead, from
http://www.cbsnews.com/stories/2003/08/21/earlyshow/contributors/emilysenay/main569618.shtml
or http://tinyurl.com/y649yb

"A recent study appearing in the August issue of Pediatrics showed 96
percent of participants do not know how to fit a bike helmet, despite
thinking it's very easy to do."

If 96% can't do use properly, can this product be called a good design?

Would you defend brakes that were as hard to properly adjust?

If so, your standards are just too low.

- Frank Krygowski

 

[[email protected]]

Ozark Bicycle wrote:
>
>
> Just recently, I helped someone adjust a helmet purchased for less than
> $20 at Wal-Mart. It was not as simple as with some more expensive
> helmets, but it *still* took less than 10 minutes.

Hmm. If it was so easy, why were you asked to help?

Again, all this is a farily minor point. When you take a product that
isn't really needed and isn't effective anyway, it's not very important
that it's hard for most people to adjust!

- Frank Krygowski

 

[[email protected]]

gds wrote:
>
> With regard to income level and ER utilization. There is a whole host
> of studies that show the relationship to be inverse. You can google up
> hundreds of them. You are imagining the wrong choice. It is not ER vs.
> home treatment (essentially no treatment). Except for very serious
> trauma it is ER vs. private medical care. When I have a minor injury I
> go to my docs office. Of course, if I was seriously injured I would be
> taken to an ER. But there are myriad studies showing that lower income
> groups use the ER for true emergencies and for primary care as they
> don't have a relationship with a primary care doc. So, this is not only
> a waste of resources as ER's are much higher cost providers than a
> docs office; but it also skew that data since many of the less serious
> injuries among the wealthier and better insured do not show up in ER
> statistics because w don't go there for that type of care. I'm not even
> going to argue this further because the number of studies that have
> shown this for the past 40 years are enormous.
^^^^

Unfortunately, you're discussing the wrong "this." As I tried to
explain above, the issue is not whether a poor person will go to the ER
instead of their private doctor when they have, say, the flu. The
issue is, when poor people and well-off people go to the ER due to an
injury, which group tends to have worse injuries?

The citation I gave said that immigrants tend to have significantly
worse injuries in that situation. The data set from Thompson & Rivara
1989 showed the same thing. And I believe we all understand that
well-off people are more likely than poor people to wear helmets.

This is the effect that will bias this proposed study. Doctors doing
simple counts are likely to say "The people with helmets more
frequently had only inconsequential injuries, so the helmets must have
protected them" whereas the real conclusion should be "The people with
helmets tended to have better insurance, so they came to the ER more
often, even for inconsequential injuries."

> And why beat the dead horse of bias? No one is arguing that if a study
> is biased it isn't worth much. So constantly repeating that mantra
> accomplishes what?

Well, I think it's obvious that there are _some_ people that don't
understand this point. We can start with the Austin City Council and
certain ER docs - but the list certainly doesn't stop there!

> However, it is not always correct to assume that because one expects
> are certain outcome they will be biased. Bias is only if they either
> design the study so that that outcome must be obtained or if they twist
> the interpretation of the data to achieve that result. having
> expectations is normal.

Hmm. Then medical researchers are wasting an awful lot of time and
money designing double-blind studies! How on earth did, say, the FDA
scientists ever conclude that the double-blind technique is necessary?


Next time a drug company has a fancy new drug to test, the FDA should
just let that drug company's physicians evaluate the patients. Let the
patients know that they've been given the drug under test, and let the
examining physician know too! None of this "compare with a placebo"
nonsense!

That should increase the number of "successful" drug trials quite a
bit!

- Frank Krygowski

 

[SMS]

Ozark Bicycle wrote:
> Frank, recently you have ceased claiming that "helmets make cycling
> more dangerous", that "helmets make it more likely you will hit your
> head", that helmet use causes "risk compensation" etc., etc. That's a
> Good Thing. But now, you are clutching at the straw that they are hard
> to adjust properly and frequently go out of adjustment, etc. It's a
> song you seem to be singing alone. If you can't properly adjust a
> helmet, see if you can find someone who can show you how to do it
> properly; there's no shame in needing instruction.
>
> What's next? Do helmets cause cancer? ;-)

I thought that he claimed that they caused salmonella poisoning.

 

[SMS]

gds wrote:

> However, it is not always correct to assume that because one expects
> are certain outcome they will be biased. Bias is only if they either
> design the study so that that outcome must be obtained or if they twist
> the interpretation of the data to achieve that result. having
> expectations is normal.

It would be abnormal to not have the expectation that their study will
show the same thing as every other study that studied the same thing.

With only a one-year study, their numbers will be different, but likely
with the same conclusion.

The hope would be that after all the data is presented, the conclusion
of the city council would be something like: "helmets reduce the
severity of injuries, and the number of fatalities, but the incidences
of accidents where a helmet makes this difference is sufficiently small
that legislation to mandate the use of helmets is unnecessary."

 

[Ozark Bicycle]

[email protected] wrote:
> Ozark Bicycle wrote:
> >
> >
> > Just recently, I helped someone adjust a helmet purchased for less than
> > $20 at Wal-Mart. It was not as simple as with some more expensive
> > helmets, but it *still* took less than 10 minutes.
>
> Hmm. If it was so easy, why were you asked to help?
>

I wasn't asked, I offered my help. My general approach in this matter
runs along the lines of "As long as you're wearing a helmet, let's make
sure it can be effective if it's needed". A lot of people do ride
around with poorly adjusted helmets. And a lot of people drive around
with poorly positioned/adjusted seatbelts. A lot of people can't
operate their PC, DVD player, etc. The fact of the matter is that
people tend not to read and/or comprehend instructions. It's not just
an issue in bicycle helmets.

<remainder snipped>

 

[Ozark Bicycle]

[email protected] wrote:

<big snip of Frankie's claptrap>

> Reading comprehension, Ozark, reading comprehension!
>

You just can't help being a condescending, insulting ass, can you,
Frankie? You're just a cradle-to-grave asshole.

<remaining claptrap snipped>