Ontario Helmet Law being pushed through

On Sun, 6 Feb 2005 23:33:43 -0500, "Riley Geary"
wrote:

Once again, you seem to be confusing an apparent safety benefit, resulting
most likely from selective recruitment of helmet users among Florida's
bicyclists, with the real thing--which remains to be determined, but is
almost certainly much less than 40%.

In the UK 25% of all cyclist fatalities are due to being crushed to
death by turning goods vehicles, most of them in London. If you
believe our helmet promotion charity that means that helmets would
prevent in excess of 100% of the balance :-)

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 CHS, Puget Sound

Can I get a cite on the Utah study ? It looks interesting

John Kane
Kingston ON

Riley Geary wrote:

bicyclists, then we not only have a reasonably coherent explanation as to
why bike helmet use has had little or no favorable impact on overall bicycle
fatality rates, but a powerful argument against imposing a MHL on bicyclists
as well.

It's a very weak argument, non-existent actually.

Look at the Louisiana data.

From 1997 to 2000, helmet use went from 100% to 52%, and motorcyclists
killed per 10,000 registrations went from 3.2 to 7.9. So helmet use fell
by a little less than 50%, and fatalities went up by 140%.

What this says is that the people that would have benefited the most
from wearing a helmet, were the ones that chose not to wear one. Not
that this is surprising.

I don't think that this is the data you want to use in any argument
againt bicycle helmet laws! The Florida data on bicycle helmet versus
non-helmeted riders showed a much smaller difference in fatality rates.

On Sun, 06 Feb 2005 16:55:16 GMT, "Steven M. Scharf"
wrote in message
. net:

Every study suffers from the possibility of self-selection.

And some are more honest about it than others. Compare Spaite:

"A striking finding was noted when the group of patients without major
head injuries (246) was analyzed separately. Helmet users in this
group still had a much lower mean ISS (3.6 vs. 12.9, p less than
0.001) and were much less likely to have an ISS greater than 15 (4.4%
vs. 32.1%, p less than 0.0001) than were nonusers. In this group, 42
of 47 patients with an ISS greater than 15 (89.4%) were not wearing
helmets. We conclude that helmet nonuse is strongly associated with
severe injuries in this study population. This is true even when the
patients without major head injuries are analyzed as a group; a
finding to our knowledge not previously described."

with the 1989 Seattle study, which compares radically different
populations of cyclists, assumes an atypical and homogeneous group to
be typical in terms of helmet wearing rate (despite co-author Rivara's
own contemporaneous street counts proving otherwise), and attributes
all the difference to the helmets themselves, a classic confusion of
cause and effect.

Guess which one is quoted by every single helmet promotion campaign?

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

On Mon, 07 Feb 2005 17:57:14 GMT, "Steven M. Scharf"
wrote in message
. net:

bicyclists, then we not only have a reasonably coherent explanation as to
why bike helmet use has had little or no favorable impact on overall bicycle
fatality rates, but a powerful argument against imposing a MHL on bicyclists
as well.

It's a very weak argument, non-existent actually.

"The results indicate that risk compensation may modify the
effectiveness of PE [protective equipment, sic.] for children engaged
in sports and leisure activities. Conversely, the findings also
suggest that those wearing PE may be a cautious subgroup." - Risk
compensation in children?s activities: A pilot study, Mok D, Gore G,
Hagel B, Mok E, Magdalinos H, Pless B. 2004. Paediatr Child Health:
Vol 9 No 5 May/June 2004.

Interestingly Pless set out to prove exactly your assertion, and ended
up concluding that risk compensation does apply to cycle helemts
specifically, as it seems to for most other forms of human activity
(well documented by Wilde and Adams).

So, where is your actual evidence for discounting risk compensation?

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

wrote:
Bill Baka wrote:


As a bicyclist who also likes to ride motorcycles I can say that a
helmet has a very negative effect on perception of ones surroundings.
This is mainly due to the effect of messing up the ability to hear
things that a full head motorcycle helmet causes. Bare headed I am

much

more able to sense my environment and correct for things as opposed

to

being encased in a head only protecting helmet.


This is true. However look at the statistics on fatalities of
motorcyclists in states that dropped their motorcycle MHLs. Not
surprising that the rates went way up, i.e. in Lousiana they went from
26 to 55, in Kentucky from 24 to 38 (this was for the year after the
repeal). Not magnitudes difference, but around 50-100% increase.

That could be due to a lot of people riding more, adding 50-100% the
number of mile ridden.

Still, motorcyclists should be free to make the decision to wear a
helmet or not, just as cyclists should. But it does no good for people
to try and claim that helmets are ineffective, when all the studies
prove otherwise.

A helmet is effective but in all truth, your entire body is at risk on
either a motorcycle or bicycle. With a car, the sheet metal takes most
of the crunch.

The bike club I was in was very pro-choice in terms of helmets, until
they were forced to require helmets due to the terms of insurance from
L.A.B.. Most people had been wearing helmets even prior to the
requirement, but it wasn't a big deal if someone showed up without one
(unless the ride leader required them).

I would side with the helmet people a little more if bicycle helmets
were more comfortable to wear, and if they were more effective. A little
design research might go a long way here.
Bill Baka

"Steven M. Scharf" wrote in message
ink.net...
Riley Geary wrote:

this
is mostly because increases in motorcycle registrations in those same
states
have also outpaced the average rate of increase in other states.

This is not true. The fatalities have _far_ outpaced the increase in
registrations. Motorcyclists Killed per 10,000 Registered have steadily
increased since the repeal of the law.

You can see the data at:

"http://www.nhtsa.dot.gov/people/injury/pedbimot/motorcycle/kentuky-la03/Law
ChgLa.html"


NHTSA has put out a fair number of pretty shoddy research reports over the
years, but you've managed to latch onto the worst part of one of their lamer
efforts, "Evaluation of the Repeal of Motorcycle Helmet Laws in Kentucky and
Louisiana, DOT HS 809 530, October, 2003."

It's interesting that you didn't direct our attention toward section IV
dealing with Kentucky, but instead chose section V dealing only with
Louisiana. At least the section dealing with Kentucky has some reasonable
looking helmet use/injury data and motorcycle registration numbers, though
it should be obvious from Table 5 (75-77% of all injured motorcyclists prior
to 1998 were listed as using helmets) that the observed helmet use survey
data presented in Table 2 can't possibly be accurate, particularly prior to
the 1998 repeal of Kentucky's MHL (96% helmet use rate among motorcyclists).
But apparently the conclusion that "Motorcyclists killed per 10,000
registered motorcycles increased from less than 7 under the universal helmet
law to more than 8 following repeal" didn't sound dramatic enough, so you
went with the section on Louisiana instead.

Unfortunately, the data presented in section V dealing with Louisiana
appears to be largely bogus. Table 7 on observed helmet use survey data,
purporting to show that essentially 100% of motorcyclists prior to the 1999
repeal of Louisiana's were using helmets, is almost certainly a fabrication
since data in table 3 of the report "An Analysis of Motorcycle Crashes 1996
to 2002" published by the Louisiana Highway Safety Commission
http://lhsc.lsu.edu/SpecializedRepor...d_5-1-03_2.pdf
indicates just 58% of all injured motorcyclists were actually using helmets
prior to 1999, which rate has only declined to 48% post-1999. Likewise, the
registration data in Table 10, supposedly from the Louisiana Dept of Public
Safety, bears no relationship at all to the same data reported via the FHWA
and BTS, and presented by NHTSA itself through its annual Traffic Safety
Fact Sheets dealing with Motorcycles:
http://www-nrd.nhtsa.dot.gov/departm.../AvailInf.html

Year Reg MC Fatalities/10,000 Reg MC (LA-DPS)
1997 60042 3.2
1998 57189 5.9
1999 64075 6.2
2000 72445 7.9

Year Reg MC Fatalities/10,000 Reg MC (NCSA)
1993 38000 7.6
1994 36000 7.8
1995 36000 7.8
1996 36000 7.8
1997 37000 5.4
1998 37000 9.5
1999 39000 9.7
2000 43000 9.3
2001 48000 11.8
2002 51000 12.9
2003 54000 12.6

The other problem here is that the LA-DPS data conveniently begins with
1997, a year with an anomalously low number of motorcycle fatalities in
Louisiana. Was this simply an innocent choice of both the data range and
data source by the author of section V, or was it deliberately chosen to
mischaracterize the increase in motorcycle fatalities per 10,000 registered
motorcycles as being much higher than it really was following repeal of
Louisiana's MHL?

Look, most of us here are opposed to MHLs for both motorcycles and
bicycles, but this is in spite of the data, because of the personal
freedom aspect. It does this cause no good to lie about reality.


And who exactly is doing the lieing about reality here?

Riley Geary

"Steven M. Scharf" wrote in message
ink.net...
Riley Geary wrote:

bicyclists, then we not only have a reasonably coherent explanation as
to
why bike helmet use has had little or no favorable impact on overall
bicycle
fatality rates, but a powerful argument against imposing a MHL on
bicyclists
as well.

It's a very weak argument, non-existent actually.


Really? Then how do you explain the demonstrated fact that in most states
with a MHL for which we have reasonably reliable helmet use data on
non-fatally injured motorcyclists, helmeted motorcyclists appear to have a
much greater chance of ending up in a potentially fatal crash than their
non-helmeted counterparts, even though they obviously have a better chance
of surviving such a crash once it occurs.

Look at the Louisiana data.

Yes, let's do that, but with an open mind this time as to the source of that
data.


From 1997 to 2000, helmet use went from 100% to 52%, and motorcyclists
killed per 10,000 registrations went from 3.2 to 7.9. So helmet use fell
by a little less than 50%, and fatalities went up by 140%.

What this says is that the people that would have benefited the most
from wearing a helmet, were the ones that chose not to wear one. Not
that this is surprising.

See my analysis of this in my previous response to you today. Needless to
say, none of this "data" stands up to close scrutiny.

OTOH, if you really want to take another look at the Louisiana data, I'll
simply point out that from 1994-98, prior to repeal of their MHL, 98
helmeted motorcyclists were killed, but only 42 non-helmeted motorcyclists;
while 2537 helmeted motorcyclists survived with non-fatal injuries, and 2109
non-helmeted motorcyclists. This gives us an odds ratio of
(98/42)*(2109/2537) = 1.94 -- meaning helmeted motorcyclists in Louisiana
were then nearly twice as likely to end up with a fatal injury relative to
non-helmet-using motorcyclists. After repeal though, from 2000-03 only 83
helmeted motorcyclists were killed, but 173 non-helmeted motorcyclists died;
while 2381 helmeted motorcyclists survived with non-fatal injuries, along
with 2637 non-helmeted motorcyclists. This gives us a completely different
odds ratio of (83/173)*(2637/2381) = 0.53 -- meaning helmeted motorcyclists
are now only half as likely to end up with a fatal injury relative to
non-helmet-using motorcyclists.

If you can explain this nearly four-fold change in the apparent
effectiveness of motorcycle helmets before and after repeal of a MHL without
invoking some form of risk compensation, I'ld be very interested in hearing
it. After all, I don't necessarily claim any of my analyses to be
infallible, let alone the Final Word on the subject, so if you have a
reasonable alternative to propose, I'ld be more than willing to consider it.


I don't think that this is the data you want to use in any argument
againt bicycle helmet laws!

I know it's not data you would want to continue treating as either reliable
or legitimate now...

The Florida data on bicycle helmet versus
non-helmeted riders showed a much smaller difference in fatality rates.


And still you haven't said a word about the Florida motorcycle helmet data
I've commented on at length, and which shows the same sort of effect with
respect to repeal of a MHL as noted above for Louisiana.

Riley Geary

Riley Geary wrote:

Year Reg MC Fatalities/10,000 Reg MC (NCSA)
1993 38000 7.6
1994 36000 7.8
1995 36000 7.8
1996 36000 7.8
1997 37000 5.4
1998 37000 9.5
1999 39000 9.7
2000 43000 9.3
2001 48000 11.8
2002 51000 12.9
2003 54000 12.6

The other problem here is that the LA-DPS data conveniently begins
with
1997, a year with an anomalously low number of motorcycle fatalities
in
Louisiana. Was this simply an innocent choice of both the data range
and
data source by the author of section V, or was it deliberately chosen
to
mischaracterize the increase in motorcycle fatalities per 10,000
registered
motorcycles as being much higher than it really was following repeal
of
Louisiana's MHL?

It was both innocent and deliberate. It was the year before the repeal,
versus the year of the repeal. Totally logical. But if you want to
average 1993-1997, then average 1998-2003, that's fine too.

7.3 per 10K with MHL versus 11.0 per 10K after the repeal. So it's only
a 51% increase in fatalities.

Sorry Riley. There is just no way you can twist the data to prove what
you're trying to prove. And it doesn't matter anyway. The states did
the right thing by repealing the MHLs, but don't kid yourself into
thinking that they did it without knowing that there'd be consequences
in the fatality rates.

b_baka wrote:

I would side with the helmet people a little more if bicycle helmets
were more comfortable to wear, and if they were more effective. A
little
design research might go a long way here.

At least in this thread, there are no people that have come out in
favor of the coercive mandatory helmet law. So you don't have to side
with anyone.

It's basically an argument over whether or not helmets have any effect
in the reduction of injuries or deaths in bicycle crashes.

Mose people recognize that it is possible to oppose mandatory helmet
laws, while at the same time recognizing the fact that helmets do have
a positive effect when crashes occur. The statistical data to support
the latter point is overwhelming and incontravertible (though each
study shows different percentages, every study supports the basic
premise).

There are really only 3-4 people that consistently claim that helmets
are worthless, apparently believing that unless they can convince
someone of this, that helmet laws will be passed. Most of us believe
that helmet laws are a bad idea despite the relatively small benefit in
terms of injury and fatality reduction. No one believes the "if it
saves one life then it's worth it," line of thinking.