I submit that on or about Sun, 17 Jul 2005 15:54:21 GMT, the person
known to the court as SMS <[email hidden]> made a statement
(<[email hidden]> in Your Honour's bundle) to
the following effect:
Quoted message said:I suggest that you go back and look at references in one of the numerous
helmet debate threads.
Just as a matter of interest, how many of those papers have you
actually read in full?
Like many other sceptics I used to be an enthusiastic advocate for
helmet use until I was actually prompted to go out and read the data
(I have several hundred papers in my helmet library now and it's far
from complete), so I'm quite happy to change my view based on the
evidence.
Quoted message said:However no amount of data will convince some people, as they will come
up with an excuse for every study.
Works both ways :-) There are six jurisdictions which have shown a
forty percentage point or greater increase in helmet use after
compulsion, not one of them shows a consequent reduction in head
injury rates. Actually, the British road safety minister said in a
letter that the Government knows of no case where cyclist safety has
improved with increasing helmet use.
One reason you get "excuses" for "every" study, of course, is that a
lot of them share common flaws. There are parallels: numerous
observational case-control studies showed that women who used combined
hormone replacement therapy were at lower risk of coronary heart
disease. The medical profession pretty much decided that CHRT
prevented CHD in women, and allowed the drugs companies to mount
clinical trials. The result showed a small but significant /increase/
in risk - the reason for the difference being down to the common
self-selection bias in the observational studies. Women who went for
HRT were more likely to be middle-class and have good diet.
Actually, a recent paper showed that five out of six widely-cited
observational studies turned out to be wrong or significantly
over-optimistic, as measured by subsequent clinical trials. It seems
that *most* observational case-control studies are wrong!
So, although I don't deny that a flawless study might exist, I've not
seen it to date. But as I say, my library is not complete.
Quoted message said:The most compelling study was a
ten-year Florida study, which looked at deaths and injuries of helmeted
versus non-helmeted cyclists. As soon as this study was brought up here,
the rationalizations began.
Which study is that? Cite, please.
Quoted message said:I just wish that people would both be intellectually honest, and not
resort to fallacious argument techniques, in defense of their position.
So do I :-)
I also wish that those who are advocating helmet use would stop
reversing the burden of proof and challenging sceptics to prove
helmets "don't work" (would you accept that drug companies should be
allowed to challenge the FDA to prove new drugs don't work, rather
than the other way around?). Case-control studies are inadmissible
for other interventions, for good reasons.
And I also wish that those who have made up their mind one way could
be content for others to make up their mind the other way. I will
stick my neck out here and suggest that there will not be more than a
handful of helmet threads in the archive that have started with anyone
saying "don't wear a helmet" (other than maybe as a joke).
I especially wish they'd stop trying to force their choice on others
by legislation. One thing that does *not* work, according to a really
substantial body of evidence, is forcing people to wear helmets.
Anyone who has read the major pro-helmet studies in detail is likely
to understand why: putting a hat on a head does not turn the wearer
into the kind of risk-averse cyclist who will wear one by choice.
Guy
--
May contain traces of irony. Contents liable to settle after posting.
http://www.chapmancentral.co.uk
85% of helmet statistics are made up, 69% of them at CHS, Puget Sound