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From: Dave Blake <>
Subject: Re: Kunich's Anti-helmet stance Was: Re: concussions?
Date: 17 Mar 1998 01:52:21 GMT

Andrew Albright writes:
>Proofs across populations?  I just quoted a study that is statistically
>significant showing helmets reduced head trauma.
>So go ahead and post the references from when you "read everything [you]
>could on the topic".  I remember last time I suggested you do this, you
>failed.  It shouldn't be that difficult.
>You are 0-1.  As a "trained scientist" you know that kind of bullshit
>doesn't walk very far on its own.
>I buy the "live free or die" argument...rather admirable, but your
>unsubstantiated "logic"-based arguments aren't very convincing so far.

You can cite studies showing that given that someone is going to
the ER, if they were wearing a helmet, there is a lower chance that
they have a head injury. And I grant you that given that you are
going to fall and hit your head, a helmet will provide some

But there is a lot more to it than that, and you know it. To
make a claim about safety you need to know both the probability
of an accident occuring, and the severity of the accident should
it occur. If there were one bicycling accident a year in which
someone hurt their head, would that justify every person in the
US wearing a helmet ? How about two ? Where and how do you draw
the line ? Two famous people have been killed skiing lately in
the US. Should I wear a helmet while I ski ? Why or why not ?

And the insidious part is that there is substantial evidence that
helmet use inhibits the use of the bicycle. How can you weigh
the positive health benefits of cycling against the potential
for harm from not wearing a helmet? What do you set as your
cost benefit tradeoff? If everyone who cycled wore a helmet but
half as many people cycled (an admitted exageration), should
people wear helmets ? Wouldn't it depend on the risk of head
injury and the severity of head injuries should they occur? It
is easy to grasp the obvious point that there are circumstances in
which helmet wearing would be beneficial (ie: I am going to fall and
hit my head), but tougher to weigh against all the factors involved
(ie: I have ridden 40-50 thousand miles this decade and have yet
to scratch my head). Given the large number of disorders that are
attributed to lack of physical activity and obesity in the US,
shouldn't some priority be given to encouraging use of the bicycle ?

Further, places in the world that see LARGE changes in adult helmet
use see NO changes in rate of head injury or fatality rate. That
alone seems to bear out the insignificance of helmet wearing in
an adult population. (NOTE: different findings have come from
adolescent helmet laws in the US).

Here are some of the things that bear out some of the points I
have been claiming. I choose not to include ER studies, but I will
claim that they show clearly that: given a cyclist is in the ER for
treatment, there is a lower chance of them having a head injury if
they wore a helmet while they were cycling.
***********From the BHSI web site,************
Statistics from Failure Analysis Associates

Injuries Associated with Example Items in 1989

(Chart copyright 1995 by FaAA, repeated here
because it is hard to read on their Web page.)

    Product                              Number of Injuries

 Motor Vehicles                              1,744,903
 Stairs, Steps, Ramps and Landings             854,500
 Bicycles and accessories                      514,700
 Beds                                          299,200
 Household Chemicals and Cleaning Products      65,900
 Doors (Not Glass)                              46,200
 Pens and Pencils                               29,900
 Money                                          28,700
 First Aid Equipment                            27,300
 Toothpicks                                      5,500
 Combs or Hairbrushes                            3,700

Note: Emergency room treated injuries projected from
Consumer Product Safety Commission data...
(rest is obscured on their page).

And more estimates from the same source:

      Estimate of Fatal Risk by Activity

Activity                 # Fatalities per 1,000,000 exposure hours
--------                 -----------------------------------------
Skydiving                                     128.71
General Aviation                               15.58
On-road Motorcycling                            8.80
Scuba Diving                                    1.98
Living (all causes of death)                    1.53
Swimming                                        1.07
Snowmobiling                                     .88
Passenger cars                                   .47
Water skiing                                     .28
Bicycling                                        .26
Flying (scheduled domestic airlines)             .15
Hunting                                          .08
Cosmic Radiation from transcontinental flights   .035
Home Living (active)                             .027
Traveling in a School Bus                        .022
Passenger Car Post-collision fire                .017
Home Living, active & passive (sleeping)         .014
Residential Fire                                 .003

Data compiled by Failure Analysis Associates, Inc.
(see Design News, 10-4-93)

*******************End BHSI web site excerpt**************************

***********From CRAG web site, ***************************************
Reduction in Cyclists in the A.C.T.

by Peter van Schaik
Cyclists Rights Action Group
26 September 1996

Ratcliffe (1993) reported that mean weekday cycle path daily volumes
in the ACT were recorded in (December) 1992 to be about one third
lower than the similar period in (November) 1991, with mean weekend
daily volumes declining by about half. This was after compulsory helmet
legislation was introduced in July 1992, compelling cyclists of all
ages to wear a helmet whilst riding a bicycle in any public place.

In 1993/94 the counts were done mainly in February. The Government
has claimed from these 1993/94 counts that cycling has increased
back to almost pre-law levels. A ministerial brief (obtained by the
Cyclists' Rights Action Group through a Freedom of Information
(FOI) request) advised the Minister for Urban Services Mr Tony
De Domenico that commuter cycling had increased by 34% since 1992
(almost back to pre- law figures). This advice is wrong.

Cycling is, obviously, a highly seasonal activity. February, being
one of the hottest times of the year in a cold Canberra climate,
is one of the most popular months for cycling and is significantly
more popular than either November or December, as shown in the
following table taken from the ACT Bicycle Volumes:

Month   B16:  Between Albert Street and  B55: Between Flynn Place and
        Commonwealth Ave Bridge, Parkes  Kaye Street, Parkes
        Weekday  Weekend  Weekly         Weekday  Weekend  Weekly
Jul-93   0.59     ****     0.65           0.89     0.82     0.89
Aug-93   0.59     0.40     0.52           0.98     0.97     0.97
Sep-93   0.71     0.63     0.68           1.07     1.33     1.14
Oct-93   1.30     1.18     1.35           0.87     1.03     0.91
Nov-93   1.43     1.09     1.46           0.51     0.49     0.50
Dec-93   ****     ****     ****           0.87     0.83     0.86
Jan-94   0.49     0.68     0.49           1.50     1.34     1.45
Feb-94   1.60     1.52     1.68           1.31     1.20     1.30
Mar-94   1.76     1.71     1.56           ****     ****     ****
Apr-94   0.86     1.08     0.93           ****     ****     ****
May-94   0.67     0.72     0.69           ****     ****     ****
Volume   655      476      594            426      374      412

**** counts not available

It is obvious that comparisons between figures for different
times of the year are not valid. However, there were four sites
counted in December 1993, rather than January or February 1994.
These can be compared with the post-law December 1992 counts and
fail to show any significant overall increase:
                               Weekly counts

Site Between           Nov 91 (prelaw)  Dec 92 (postlaw)  Dec 93
Challis St/Cowper St    3153             1829              1351
Adelaide Ave/Caruthers  1852             1485              1724
Luxton/M'Dermott        2977             1549              1716
AIS/Dryandra St         3521             2900              3019
Total                  11503             7763              7810

Comparisons of those few sites with figures available for the
same months, show a total count of 7763 for 1992/93 versus 7810
for 1993/94. This is an increase of only 0.6%, and is still 32%
less than the pre-law figures.

The ministerial brief also mentioned a helmet wearing rate of 90%.
This figure is based on data from early 1994. However, anecdotal
evidence sugggests that the helmet wearing rate may have recently
dropped to as low as 50%. Perhaps another study should be
conducted on this, and any future surveys on numbers of cyclists
should also take into account helmet wearing rates, since any
increase in cyclists may well be purely the result of lax law
enforcement. It is also possible that the activities of
anti-helmet law advocates may be undermining public faith in
helmets as the solution to bicycle safety, leading to more
cyclists but lower helmet wearing rates.

There is no evidence to support the claim that cycling has
increased back to pre-law levels after the initial decline.

W.J. (Bill) Curnow
D.L. Robinson (UNE)

ACT Bicycle Volumes; Trends, Variations, Survey Results,
Helmet Wearing And Cyclist's Characteristics, 1991 - 1993/94;
Report prepared by the Traffic Monitoring Unit, ACT City Services,
Department of Urban Services, PO Box 158 Canberra ACT 2601, Australia.

Ratcliffe, P., Bicycling in the ACT - a survey of bicycle riding
and helmet wearing in 1992, ACT
Department of Urban Services, Canberra, 1993.
***********End CRAG web site excerpt**********************************

Scuffham PA; Langley JD.
Trends in cycle injury in New Zealand under voluntary helmet use.
Accident Analysis and Prevention, 1997 Jan, 29(1):1-9.

Abstract: Twelve months before the wearing of a cycle helmet
was to become mandatory in New Zealand, a substantial proportion
of cyclists on public roads had 'voluntarily' adopted wearing a
helmet. Helmet wearing rates had increased up to 84, 62 and 39%
for primary school children, secondary school children, and adults
respectively by the end of the period of interest. The purpose
of this study was to examine the serious injury trends for three
age groups of cyclists: primary school age (5-12 years),
secondary school age (13-18 years), and adults (over 18 years)
admitted to selected public hospitals between 1980 and 1992;
twelve months before the introduction of helmet legislation.
Serious injury was defined as 'admitted to hospital' then
disaggregated by type of crash and length of stay. Statistical
models were constructed that included the proportion of people
admitted to hospital with a head injury, then analysed using
Poisson regression. Results revealed that the increased helmet
wearing percentages has had little association with serious
head injuries to cyclists as a percentage of all serious
injuries to cyclists for all three groups, with no apparent
difference between bicycle only and all cycle crashes.
Discussion of the results includes possible explanations for
the absence of a decline in the percentage of serious head
injury among cyclists as cycle helmet wearing has increased.
Hansen P; Scuffham PA.
The cost-effectiveness of compulsory bicycle helmets in New Zealand.
Australian Journal of Public Health, 1995 Oct, 19(5):450-4.

Abstract: This paper examines the cost-effectiveness for
primary school children (age 5-12 years), secondary school
children (13-18 years) and adults (over 18 years) of the
legislation enacted on 1 January 1994 requiring road-cyclists
in New Zealand to wear helmets. The cost to cyclists not in
possession of a helmet before they became compulsory of
either obtaining one or quitting cycling was compared with
the number of deaths and hospitalisations expected to be
prevented over the average life of a helmet. Corresponding
to Victorian and United States estimates of the efficacy of
cycle helmets at preventing serious head injuries, the cost
per life saved was $88 379 to $113 744 for primary school
children, $694 013 to $817 874 for secondary school children,
and $890 041 to $1 014 850 for adults (New Zealand dollars =
approximately 0.95 Australian dollars). The cost per
hospitalisation avoided was $3304 to $4252, $17 207 to
$20 278, and $49 143 to $56 035 respectively. These estimates
are extremely sensitive to the estimated efficacy of helmets
at protecting cyclists. Mainly anecdotal evidence for New
Zealand suggests that they are not to be very effective at
preventing serious head injuries; future research into the
change in injury patterns as a result of the helmet
regulation would be valuable. Nonetheless, the ranking of
the abovementioned estimates does not contradict the policy
in some parts of the world requiring helmets for children
and/or teenagers, but not adults.
Robinson DL.
Head injuries and bicycle helmet laws.
Accident Analysis and Prevention, 1996 Jul, 28(4):463-75.

Abstract: The first year of the mandatory bicycle helmet
laws in Australia saw increased helmet wearing from 31%
to 75% of cyclists in Victoria and from 31% of children
and 26% of adults in New South Wales (NSW) to 76% and 85%.
However, the two major surveys using matched before and
after samples in Melbourne (Finch et al. 1993; Report No. 45,
Monash Univ. Accident Research Centre) and throughout
NSW (Smith and Milthorpe 1993; Roads and Traffic Authority)
observed reductions in numbers of child cyclists 15 and 2.2
times greater than the increase in numbers of children
wearing helmets. This suggests the greatest effect of the
helmet law was not to encourage cyclists to wear helmets,
but to discourage cycling. In contrast, despite increases
to at least 75% helmet wearing, the proportion of head injuries
in cyclists admitted or treated at hospital declined by
an average of only 13%. The percentage of cyclists with
head injuries after collisions with motor vehicles in
Victoria declined by more, but the proportion of head
injured pedestrians also declined; the two followed a
very similar trend. These trends may have been caused
by major road safety initiatives introduced at the same
time as the helmet law and directed at both speeding and
drink-driving. The initiatives seem to have been remarkably
effective in reducing road trauma for all road users,
perhaps affecting the proportions of victims suffering
head injuries as well as total injuries. The benefits of
cycling, even without a helmet, have been estimated to
outweigh the hazards by a factor of 20 to 1 (Hillman 1993. Cycle
helmets-the case for and against. Policy Studies Institute, London).
Consequently, a helmet law, whose most notable effect was
to reduce cycling, may have generated a net loss of health
benefits to the nation. Despite the risk of dying from head
injury per hour being similar for unhelmeted cyclists and
motor vehicle occupants, cyclists alone have been required
to wear head protection. Helmets for motor vehicle occupants
are now being marketed and a mandatory helmet law for these
road users has the potential to save 17 times as many people
from death by head injury as a helmet law for cyclists without
the adverse effects of discouraging a healthy and pollution
free mode of transport.

Dave Blake

From: (Lee Green MD MPH)
Newsgroups: rec.bicycles.misc
Subject: Re: How cyclists get killed
Date: Sun, 03 May 1998 01:51:40 GMT

In article <6ifbor$lif$>, (Frank
Krygowski) wrote:

> ...Certainly, a high school student would
> understand that it makes no sense to spout off wild guesses when you can
> look up the statistics.
> About your list: of course, "no helmet" does not kill anybody.  You don't
> have one on now, and you're doublessly alive.  Worse, bike helmets haven't
> been shown to save lives to any statistically significant degree.  They
> protect against minor bumps, that's all.

Frank, you're wrong.  I'm not interested in the incessant helmet flame
wars, as the participants therein have no detectable interest in
evidence-based evaluation, but if you have the interest in real data you
suggest by the first paragraph I quoted above please examine the actual
facts. I've included the relevant clinical study citations below.  These
are the quality studies, weeding out the speculative and the public
health-we-know-what's-good-for-you nonsense.

The clinical data are clear: Snell-grade bicycle helmets prevent about
one-third of deaths and two-thirds of serious injuries (those which
require neurosurgery or result in measurable neurological injury).  These
results are remarkably consistent across studies, even those of different
methodologies.  This point is particularly telling, as spurious or biased
results generally don't replicate when you shift from longitudinal to
cross-sectional or otherwise change methodology.

That's a significant reduction in a risk which isn't very great to begin
with, of course; few cyclists are killed even without helmets.  The NNT,
or the odds that a helmet will save you if you wear it your whole riding
career vs. never wear one at all, are somewhere between 1 in 500 and 1 in
2000.  Myself, I wear mine because it's a cheap, easy precaution and I
don't want to take any more chance of ending up sitting in a wheelchair
drooling on myself than I have to.  But realistically the risk is small,
unless you're racing or hammering trails on the fat tyre bike.  (If you're
MTBing properly, it's not a matter of whether you'll crush a helmet, but
of how often!)

As for what really kills cyclists, the data there are clear too.
1) Failure to yield on the part of cyclists, mostly either running stop
signs/lights or riding out into traffic from driveways (remember, kids are
the cyclists killed most often).
2) Failure to yield on the part of cars, as in ordinary motorist carelessness.

Far and away the majority of collisions are at or near right angles, as
cyclists are entering/leaving lanes.  The fear we all have of being hit
from behind by the Bud-guzzling anus in the pickup truck is only about 3%
of collisions.

Outrages such as drunks plowing into a paceline are headline-grabbers, but
rare.  They should of course be sold to shark fishermen for live bait, but
they're not a frequent cause of cyclist deaths.

Williams M
The protective performance of bicyclists' helmets in accidents.
In: Accid Anal Prev (1991 Apr-Jun) 23(2-3):119-31

Dorsch MM  Woodward AJ  Somers RL
Do bicycle safety helmets reduce severity of head injury in real
In: Accid Anal Prev (1987 Jun) 19(3):183-90

Thompson DC  Thompson RS  Rivara FP  Wolf ME
A case-control study of the effectiveness of bicycle safety helmets
  in preventing facial injury.
In: Am J Public Health (1990 Dec) 80(12):1471-4

Wasserman RC  Waller JA  Monty MJ  Emery AB  Robinson DR
Bicyclists, helmets and head injuries: a rider-based study of helmet
  use and effectiveness.
In: Am J Public Health (1988 Sep) 78(9):1220-1

Ginsberg GM  Silverberg DS
A cost-benefit analysis of legislation for bicycle safety helmets in
In: Am J Public Health (1994 Apr) 84(4):653-6

Wasserman RC  Buccini RV
Helmet protection from head injuries among recreational bicyclists.
In: Am J Sports Med (1990 Jan-Feb) 18(1):96-7

Maimaris C  Summers CL  Browning C  Palmer CR
Injury patterns in cyclists attending an accident and emergency
  department: a comparison of helmet wearers and non-wearers [see
In: BMJ (1994 Jun 11) 308(6943):1537-40

Maimaris C  Summers CL  Browning C  Palmer CR
Injury patterns in cyclists attending an accident and emergency
  department: a comparison of helmet wearers and non-wearers [see
In: BMJ (1994 Jun 11) 308(6943):1537-40

Thomas S  Acton C  Nixon J  Battistutta D  Pitt WR  Clark R
Effectiveness of bicycle helmets in preventing head injury in
  children: case-control study [see comments]
In: BMJ (1994 Jan 15) 308(6922):173-6

Waters EA
Should pedal cyclists wear helmets? A comparison of head injuries
  sustained by pedal cyclists and motorcyclists in road traffic
In: Injury (1986 Nov) 17(6):372-5

Spaite DW  Murphy M  Criss EA  Valenzuela TD  Meislin HW
A prospective analysis of injury severity among helmeted and
  nonhelmeted bicyclists involved in collisions with motor vehicles.
In: J Trauma (1991 Nov) 31(11):1510-6

McDermott FT  Lane JC  Brazenor GA  Debney EA
The effectiveness of bicyclist helmets: a study of 1710 casualties
  [see comments]
In: J Trauma (1993 Jun) 34(6):834-44; discussion 844-5

Bjornstig U  Ostrom M  Eriksson A  Sonntag-Ostrom E
Head and face injuries in bicyclists--with special reference to
  possible effects of helmet use.
In: J Trauma (1992 Dec) 33(6):887-93

Thompson RS  Rivara FP  Thompson DC
A case-control study of the effectiveness of bicycle safety helmets
  [see comments]
In: N Engl J Med (1989 May 25) 320(21):1361-7

Rivara FP  Thompson DC  Thompson RS  Rogers LW  Alexander B  Felix D
  Bergman AB
The Seattle children's bicycle helmet campaign: changes in helmet use
  and head injury admissions.
In: Pediatrics (1994 Apr) 93(4):567-9

McDermott FT
Helmet efficacy in the prevention of bicyclist head injuries: Royal
  Australasian College of Surgeons initiatives in the introduction of
  compulsory safety helmet wearing in Victoria, Australia.
In: World J Surg (1992 May-Jun) 16(3):379-83

Lee Green MD MPH          Disclaimer: My postings are my doing, not
Family Practice           a service of nor in any way the
University of Michigan    responsibility of the University of        Michigan.

Delete the Z from my e-mail address, it's just there to foil spambots.

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