gds wrote:
> [email protected] wrote:
> <snip>
>
>
> > FWIW, I know one ER doc very well. I won't destroy his privacy by
> > giving his name, but he lives in a state that fairly recently
> > instituted a MHL for kids. His judgement, based on ER presentations
> > he's seen? The MHL made no noticeable difference. He dismisses it as
> > worthless.
>
> Sure and I know a couple pretty well who take the opposite view.
> Individually I give a big discount to all of them but I put a much
> better chance of "being right" when you look at the opinions held by a
> large number
That depends on how those ER docs arrived at their opinions.
Specifically, if you had a large number of ER docs who became convinced
of serious helmet benefit only through their own spontaneous
observations of lots of patients, without ever having read things like
"Helmets prevent 85% of head injuries," that would be noteworthy. But
that's not the case.
My bet is that almost every ER doc in America has been repeatedly fed
the "85%" nonsense. And my bet is that almost none of them have had
time to check the validity of that ultra-common claim. It's just one of
the factoids that shows up - over and over - in the literature they
skim quickly. As such, it probably convinces many ER docs - wrongly.
And of course, they never hear that there's a controversy, let alone
hear details of the helmet skeptic case. (The skeptic's position
doesn't make anyone money, so it's essentially squelched.)
And incidentally, if you take the number of serious bike head injuries
per year in the US, divide by the number of ER doctors, you'll find
that each doctor sees very, very few serious bike head injuries, either
helmeted or non-helmeted. They see many times more auto HI and
pedestrian HI - but the trauma they observe in those folks, plus the
propaganda about bike HI and bike helmets, distorts their viewpoints.
> Without some other training we agree that ER doc's can not speak to the
> efficacy of helmet design nor , based soley on their experience can
> they speak about what is occurring in the larger world. Agreed?
Agreed.
> However they might make a statement like (not should but might) "I've
> seen lots of head injuries in cyclists over the years. I make it apoint
> to ask if the injured rider was wearing a helmet. My clinical judgement
> is that the injuries among helmet wearers is on average less severe
> than among non helmet wearers."
They might, but it's unlikely that they could make such a claim
honestly. At least, not if we insert the term "serious" before the
terms "head injuries in cyclists." Nor if we replace "head injuries"
with "brain injuries."
Consider, in the original "85%" study (Thompson & Rivara, 1989) 73% of
what they termed "head injuries" were cuts, scratches, minor bruises,
etc. They affected ears, chins, noses, etc. T&R claimed, with
admirable precision, that these were "head injuries" because ears,
chins, noses, etc. are part of the head. But of course, everyone
reading of their findings imagine they dealt with a large number of
brain injuires - probably serious ones.
In actual fact, less than 2% of the subjects had brain injuries beyond
a mild concussion - the kind for which they send you home under your
wife's care.
Again: Even serious concussions are rare cycling events. Worse brain
injuries are truly rare, and are greatly outnumbered by serious brain
injuries from motoring, walking, falling around the house, etc. The
typical ER doc won't even be able to remember lots of serious cycling
brain injuries.
Try it! Ask an ER doc how many serious brain injuries he's seen in the
past ten years. Then ask him about the most common cause. And the
second most common cause. And the third.
Then ask him how many seriously brain injured cyclists he's seen.
I've done this, with both ER doctors and with brain injury rehab
specialists. It's an interesting exercise. My favorite quote: "Let's
see - in all seven years? Well, there was one cyclist. He was a
racer."
IOW, he was probably wearing a helmet.
> Frank, you feel that helmets have minimal efficacy but you say that you
> would use them in such activites as crits, gnarly single track, tec.
> So, you must feel they have "some" value.
Actually, I think I said I'd wear one if I were forced to do those
things.
But yes, I think they have _some_ protective value, in situations where
linear head impacts are likely, and where such impacts are likely to be
of such low force that they are within the pitiful design standards.
Here's the rub: I think it's very common for people to overestimate
their protection, then subject themselves to increased risks that are
greater than the protection levels. And in that situation, I think the
people are likely to be worse off.
> I think most of us live in
> this grey world but are in differing shades of that gray. So, it really
> would be a good thing to have better data to understand the value of
> helmets better and thus we can all make better choices.
Yes - or lack of value, as the case may be. I'm all for knowledge and
education.
> Those that
> attack such inquisitiveness with the anti MHL tirades aren't
> accomplishing much other than creating lots of annoyance.
I'm not sure about your phrase "attack such inquisitiveness." I'd be
happier if everyone would learn as much about this as they possibly
could.
As I see it, there are many people who learn nothing beyond the crudest
propaganda: "Never cycle without a helmet. Helmets prevent 85% of
head injuries. A simple fall off your bike can make you a vegetable."
They don't think about this; they just accept it. Unfortunately, they
may repeat it and spread the nonsense.
There are a few True Believers who think any questioning of that dogma
is heresy. You can spot them by their _lack_ of inquisitiveness, and
their insults to those who take the time to learn.
And then there are those who have actually studied the issue, and
learned enough to reach their own decision. AFAIK, every person who
has studied this issue in detail has moved toward at least some
skepticism of helmet claims. The ones who have studied it most
thoroughly have adopted the most skeptical attitudes.
So please, inquire. I certainly won't attack inquisitiveness!
- Frank Krygowski
