Re: New BMA briefing paper. WARNING: Long, contains H word.



P

Phil Armstrong

Guest
Just zis Guy, you know? <[email protected]> wrote:
> I'd post a link but didn't get sent one, only the document.
> Authorship is attributed to Andrew Curran, of BeHIT, which tells you
> everything you need to know. I recommend vicious use of irony.


I particularly liked the way they liberally sprinkled emotive case
studies througout the paper. It's a good piece of PR work.

Interesting that they feel they have to at least acknowlege the risk
compensation criticisms, rather than dismiss them out of hand:

> Risk compensation theory
> Hypotheses on risk homeostasis and compensation are based on
> assumptions that persons adapt their behaviour toward greater or
> lesser risk in relation to how they subjectively perceive risk. This
> has been one of the arguments used against the introduction of
> mandatory cycle helmet wearing. Some opponents to legislation
> believe that cyclists who opt to use a helmet may feel safer (that
> is, they may perceive less risk of being injured as a result of a
> crash), and this may lead them to use more careless cycling
> behaviours. Spanish research (where legislation exists for mandatory
> helmet wearing) did not find evidence of the existence of a strong
> risk compensation mechanism among helmeted cyclists. [Reference 19]

[snip]
> 19. Lardelli-Claret P., de Dios Luna-del-Castillo J.,
> Jiminez-Moleon J. J., Garcia Martin M., Bueno-Cavinallas A &
> Galvez-Vargas R (2003), Risk compensation theory and voluntary
> helmet use by cyclists in Spain, Injury Prevention, 9, 128-132


Interestingly, the conclusion of this paper states:

"The results suggest that the subgroup of cyclists with a higher
risk of suffering a traffic crash are also those in which the
health consequences of the crash will probably be higher. Although
the findings do not support the existence of a strong risk
compensation mechanism among helmeted cyclists, this possibility
cannot be ruled out."

A few quotes:

"What are the implications of our findings regarding risk
compensation theory? Clearly, their usefulness in clarifying this
question is limited." (P131)

"These considerations prevent us from making definite statements
concerning the validity of risk compensation theory. Evidently, our
results do not support the existence of a strong risk compensation
mechanism in connection with voluntary helmet use in Spain,
although they obviously cannot rule out that such a mechanism may
operate." (P132)

What the paper actually showed was that people who don't wear helmets
tend to commit more infractions of the rules of the road which lead to
them having accidents. That's the only conclusion they could
reasonably draw from the data.

Of course, the BMJ position paper says nothing which is actually
dishonest about the conclusions, but to quote it at all in this
context is, I believe, meant to imply that the paper supports the case
that risk compensation as a result of helmet wearing does not
occur. The paper makes no such claims.

Phil

--
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A

Andy Leighton

Guest
On Wed, 19 Mar 2008 10:57:25 +0000,
Phil Armstrong <[email protected]> wrote:
> Just zis Guy, you know? <[email protected]> wrote:
>> I'd post a link but didn't get sent one, only the document.
>> Authorship is attributed to Andrew Curran, of BeHIT, which tells you
>> everything you need to know. I recommend vicious use of irony.

>
> I particularly liked the way they liberally sprinkled emotive case
> studies througout the paper. It's a good piece of PR work.


Interesting how the author is someone with a conflict of interest.
Surely someone without a dog in the fight would be the best person
to write a balanced position paper.

[snip]

> Of course, the BMJ position paper says nothing which is actually
> dishonest about the conclusions, but to quote it at all in this
> context is, I believe, meant to imply that the paper supports the case
> that risk compensation as a result of helmet wearing does not
> occur. The paper makes no such claims.


I would consider that intellectually dishonest.

--
Andy Leighton => [email protected]
"The Lord is my shepherd, but we still lost the sheep dog trials"
- Robert Rankin, _They Came And Ate Us_