H
Howard
Guest
Just got this e-mail from Malcolm Wardlaw regarding the BMA's chnage
of policy on polystyrene hats..
As many of you will already be aware, the British Medical Association
has suddenly changed its position on cycle helmets - the BMA now
supports compulsory use of helmets by both adults and children. The
paper justifying this decision may be found at:
http://www.bma.org.uk/ap.nsf/Content/cyclehelmetslegis?OpenDocument&High
The original position of the BMA was arrived at in 1999 as a result of
extensive gathering of evidence from many points of view. The decision
not to make helmets compulsory was fully explained in a report called
Cycle Helmets. This was an open process. The result was a reasonably
balanced presentation of the evidence then available, although it was
lacking in effective treatment of the issue of risk in cycling
(actually very low).
The change of stance has been, by comparison, a closed process sprung
as a fait accompli. The new policy in most respects rejects the
findings of the original study, yet in general on the basis of
evidence already available in 1999! I am distributing this critique of
the pro-compulsion paper to interested parties, notably doctors who
may be members of the BMA, in order to ensure that you become aware of
what is being done in your name. You may be inclined to object to the
sudden change of heart by the BMA.
There are some specific points I would like to emphasise, on the basis
of my own knowledge:
1. The paper begins by creating the impression that there is large
support for a cycle helmet law in the medical profession. In support
of this, it cites a single communication from a single doctor.
However, the BMJ carried out an opinion poll of its readership in
2002. This showed some support for a cycle helmet law, but roughly
equal support for a pedestrian helmet law for children. The
respondents showed far higher support for measures against bad driving
and reduced speed limits to reduce danger at source. The poll results
can be found at:
bmj.bmjjournals.com/cgi/content/full/324/7346/1107/DC1?ck=nck
These results do not justify the claim that doctors want a cycle
helmet law. If the BMA wishes to alter its stance on an important
public health issue, it should do a professional job of it and poll
its members openly.
2. The paper rejects evidence that helmet laws suppress cycling,
especially by children. The reasoning is that experience in Australia
is "out of date". In support of this, the case of Ontario is cited,
where legislation apparently did not suppress child cyclists. There is
a simple reason for this; the Ontario law was never enforced. If a law
isn't enforced, it can't deter cycling, can it? The evidence that
helmet laws deter cycling is so overwhelming that one could write a
paper on the topic alone. Cycle use in Australia is still below, or
hardly above, what it was in 1990 (before laws were passed) when
population increase is accounted for. In Western Australia, the
population has increased by 33% since 1990, but cycle counts only rose
above pre-law levels again in the last couple of years. Cycle use was
growing in WA before the law was passed - the law destroyed that
growth permanently. Those interested are recommended to see
www.cyclehelmets.org for a litany of examples. By taking Ontario as an
example to "prove" helmet legislation does not suppress cycle use, the
BMA stray into the realm of intellectual corruption. See:
Burdett A. Efficacy of cycle helmets and ethical arguments for
legislation. J R Soc Med 2004;97:503.
3. In justifying the "need" for a helmet law, the paper cites various
injury figures. These appear large, but only because so many slight
injuries are captured. In reality, there are about 3,000 serious
injuries in road cycling accidents per year, and 130 deaths. This
works out at on average 1,000 years of cycling by the cyclist
population per serious injury, 3,000 years per serious head injury,
and about 20,000 years per death. In other words, cycling is a low
risk activity and puffing out the figures by including a mass of
slight injuries does not change that. The cycling environment in
Britain presents risks comparable, or less, than driving in France.
The paper claims that there are more than 50 child cyclist deaths a
year in Britain. This is not correct. There are about 20-25 deaths in
road accidents (which are accurately reported by the Police, if less
so by coroners), of which approx. 15 will have suffered fatal head
injury. Contrary to the impression given, pedestrians are just as
prone to serious or fatal head injury as cyclists, or perhaps a little
more so. In addition to the 15 on-road deaths, there will be a small
number of off-road deaths.
The pedestrian population faces higher risks per mile travelled than
cyclists, by a factor of 1.6, and pedestrians are far more vulnerable
than cyclists, adults pedestrians being about twice as likely to be
killed in a reported road accident than adult cyclists.
The reality is that the actual risk in cycling is low and does not
warrant draconian measures imposed at the individual level. The best
way ahead is to increase cycle use, which makes it safer anyway, and
provide more effective cycle training and sensible advice on when a
helmet may provide some benefit. A cycle helmet is not intended to
provide protection in a road accident. It is fundamentally unethical
of the BMA to propose helmet legislation as a road safety measure.
4. In support of the effectiveness of legislation, the paper cites a
number of claims about helmets preventing brain injuries and helmet
laws reducing deaths and serious injuries. Reductions in deaths and
head injuries after helmet laws have always run in line with
prevailing trends for pedestrians. The Victoria helmet law is often
cited as a success, but it was introduced along with measures against
speeding and drunk driving. Pedestrian deaths fell 45% in the first
year of the cycle helmet law. Pedestrian hospital admissions for
concussion fell by 28% and 75% in the first and second year of the
cycle helmet law, respectively - pretty much the same as the result
for cyclists.
Careful follow up studies have failed to produce any convincing
evidence that helmet laws reduced serious injuries in the cyclist
population. This point is carefully dealt with in presentation
material that may be found at the web site of the Cross Party Cycling
Group of the Scottish Parliament (note that this material has just
been revised and a new version will be placed in the next few days).
www.scottish.parliament.uk/msp/crossPartyGroups/groups/cpg-cycle.htm
The large discrepancy between predictive observational studies,
reporting 60-75% prevention of brain injury, and the null results of
legislation is easily explained. Observational studies are based on
samples drawn from two totally different groups: those who do
self-select to take a treatment (usually a minority) and those who do
not (usually the vast majority). Inevitably confounding social factors
have such a massive influence that the results may mean very little.
The current crisis of confidence in observational epidemiology arises
from similar experience with Hormone Replacement Therapy and vitamin
supplements. The problem of unreliable science has become acute in the
cycle helmet issue because proponents of helmets and helmet laws
absolutely refuse to face up to the realities of the situation.
PERSONAL VIEW.
I finish with this personal view. The BMA has acted with inexcusable
arrogance in this matter. The decision has been taken behind closed
doors, the membership has not been effectively informed (there is no
mention of the change of policy in the current edition of the BMJ),
the evidence presented is so selective as to amount to intellectual
corruption, especially with regard to the denial of the deterrence of
cycling by legislation, on the basis of a single province where the
law was never enforced. I would hope that those reading this will
likewise feel outraged and make their feelings known to the BMA.
Kind regards,
Malcolm Wardlaw.
of policy on polystyrene hats..
As many of you will already be aware, the British Medical Association
has suddenly changed its position on cycle helmets - the BMA now
supports compulsory use of helmets by both adults and children. The
paper justifying this decision may be found at:
http://www.bma.org.uk/ap.nsf/Content/cyclehelmetslegis?OpenDocument&High
The original position of the BMA was arrived at in 1999 as a result of
extensive gathering of evidence from many points of view. The decision
not to make helmets compulsory was fully explained in a report called
Cycle Helmets. This was an open process. The result was a reasonably
balanced presentation of the evidence then available, although it was
lacking in effective treatment of the issue of risk in cycling
(actually very low).
The change of stance has been, by comparison, a closed process sprung
as a fait accompli. The new policy in most respects rejects the
findings of the original study, yet in general on the basis of
evidence already available in 1999! I am distributing this critique of
the pro-compulsion paper to interested parties, notably doctors who
may be members of the BMA, in order to ensure that you become aware of
what is being done in your name. You may be inclined to object to the
sudden change of heart by the BMA.
There are some specific points I would like to emphasise, on the basis
of my own knowledge:
1. The paper begins by creating the impression that there is large
support for a cycle helmet law in the medical profession. In support
of this, it cites a single communication from a single doctor.
However, the BMJ carried out an opinion poll of its readership in
2002. This showed some support for a cycle helmet law, but roughly
equal support for a pedestrian helmet law for children. The
respondents showed far higher support for measures against bad driving
and reduced speed limits to reduce danger at source. The poll results
can be found at:
bmj.bmjjournals.com/cgi/content/full/324/7346/1107/DC1?ck=nck
These results do not justify the claim that doctors want a cycle
helmet law. If the BMA wishes to alter its stance on an important
public health issue, it should do a professional job of it and poll
its members openly.
2. The paper rejects evidence that helmet laws suppress cycling,
especially by children. The reasoning is that experience in Australia
is "out of date". In support of this, the case of Ontario is cited,
where legislation apparently did not suppress child cyclists. There is
a simple reason for this; the Ontario law was never enforced. If a law
isn't enforced, it can't deter cycling, can it? The evidence that
helmet laws deter cycling is so overwhelming that one could write a
paper on the topic alone. Cycle use in Australia is still below, or
hardly above, what it was in 1990 (before laws were passed) when
population increase is accounted for. In Western Australia, the
population has increased by 33% since 1990, but cycle counts only rose
above pre-law levels again in the last couple of years. Cycle use was
growing in WA before the law was passed - the law destroyed that
growth permanently. Those interested are recommended to see
www.cyclehelmets.org for a litany of examples. By taking Ontario as an
example to "prove" helmet legislation does not suppress cycle use, the
BMA stray into the realm of intellectual corruption. See:
Burdett A. Efficacy of cycle helmets and ethical arguments for
legislation. J R Soc Med 2004;97:503.
3. In justifying the "need" for a helmet law, the paper cites various
injury figures. These appear large, but only because so many slight
injuries are captured. In reality, there are about 3,000 serious
injuries in road cycling accidents per year, and 130 deaths. This
works out at on average 1,000 years of cycling by the cyclist
population per serious injury, 3,000 years per serious head injury,
and about 20,000 years per death. In other words, cycling is a low
risk activity and puffing out the figures by including a mass of
slight injuries does not change that. The cycling environment in
Britain presents risks comparable, or less, than driving in France.
The paper claims that there are more than 50 child cyclist deaths a
year in Britain. This is not correct. There are about 20-25 deaths in
road accidents (which are accurately reported by the Police, if less
so by coroners), of which approx. 15 will have suffered fatal head
injury. Contrary to the impression given, pedestrians are just as
prone to serious or fatal head injury as cyclists, or perhaps a little
more so. In addition to the 15 on-road deaths, there will be a small
number of off-road deaths.
The pedestrian population faces higher risks per mile travelled than
cyclists, by a factor of 1.6, and pedestrians are far more vulnerable
than cyclists, adults pedestrians being about twice as likely to be
killed in a reported road accident than adult cyclists.
The reality is that the actual risk in cycling is low and does not
warrant draconian measures imposed at the individual level. The best
way ahead is to increase cycle use, which makes it safer anyway, and
provide more effective cycle training and sensible advice on when a
helmet may provide some benefit. A cycle helmet is not intended to
provide protection in a road accident. It is fundamentally unethical
of the BMA to propose helmet legislation as a road safety measure.
4. In support of the effectiveness of legislation, the paper cites a
number of claims about helmets preventing brain injuries and helmet
laws reducing deaths and serious injuries. Reductions in deaths and
head injuries after helmet laws have always run in line with
prevailing trends for pedestrians. The Victoria helmet law is often
cited as a success, but it was introduced along with measures against
speeding and drunk driving. Pedestrian deaths fell 45% in the first
year of the cycle helmet law. Pedestrian hospital admissions for
concussion fell by 28% and 75% in the first and second year of the
cycle helmet law, respectively - pretty much the same as the result
for cyclists.
Careful follow up studies have failed to produce any convincing
evidence that helmet laws reduced serious injuries in the cyclist
population. This point is carefully dealt with in presentation
material that may be found at the web site of the Cross Party Cycling
Group of the Scottish Parliament (note that this material has just
been revised and a new version will be placed in the next few days).
www.scottish.parliament.uk/msp/crossPartyGroups/groups/cpg-cycle.htm
The large discrepancy between predictive observational studies,
reporting 60-75% prevention of brain injury, and the null results of
legislation is easily explained. Observational studies are based on
samples drawn from two totally different groups: those who do
self-select to take a treatment (usually a minority) and those who do
not (usually the vast majority). Inevitably confounding social factors
have such a massive influence that the results may mean very little.
The current crisis of confidence in observational epidemiology arises
from similar experience with Hormone Replacement Therapy and vitamin
supplements. The problem of unreliable science has become acute in the
cycle helmet issue because proponents of helmets and helmet laws
absolutely refuse to face up to the realities of the situation.
PERSONAL VIEW.
I finish with this personal view. The BMA has acted with inexcusable
arrogance in this matter. The decision has been taken behind closed
doors, the membership has not been effectively informed (there is no
mention of the change of policy in the current edition of the BMJ),
the evidence presented is so selective as to amount to intellectual
corruption, especially with regard to the denial of the deterrence of
cycling by legislation, on the basis of a single province where the
law was never enforced. I would hope that those reading this will
likewise feel outraged and make their feelings known to the BMA.
Kind regards,
Malcolm Wardlaw.
