Bike Helmets: Statistical Aspects
by Claire Morissette
Are you an innovator or a rebel?
Many studies took a close look at the debate on the wearing of helmets.
Let's look at some conclusions from these findings, conclusions that
divide the cyclist population in different categories.
Perhaps you'll be surprised to learn that, in its strategic approach to
general helmet wearing, Quebec's Automobile Insurance Society (SAAQ)[auto insurance corporation] puts
the cyclist crowd in 5 categories, according to their attitude when facing
the change: the innovators, the precocious adoptors, the precocious
majority, the late majority, and the rebels. These concepts are taken
from a more general theory called the "theory of the spreading of
innovations."
According to this theory, Claude Dussault (SAAQ) explains that the
adoption of an innovation follows a rhythm [pattern] that depends on psychological
characteristics of each of the above 5 groups, a rhythm that is stimulated
through different means. The innovators are "highly educated, curious and
informed, and possess a leaning for what is new"; if you were wearing a
helmet in 1988 in Quebec you were amongst this 2.5% of the cyclist crowd.
The precocious adoptors are also fast and react as soon as the adverts
are shown; this category made the popularity of the helmet jump to 15% in
1991, in some places in Quebec. As for the precocious majority a more
sustained sensibilization campaign is needed before this group modifies
its behaviour; the innovation theory estimates that 34% of the population
are in this group. Next we have the late majority, more sceptical, that
will only be convinced through legislation; estimates sizes this group as
being another 34% of the population who'll change their behaviour as soon
as laws will enforce the wearing of helmets. Last, we got the rebels,
"with inferior socio-economical status, less educated, living in the
past"; for this last group, the last 16%, constraints are necessary.
Amongst them and even with police intervention and tickets, 5% will always
remain delinquents (1).
Voila, dear cyclists, how the SAAQ considers the cyclist clientele
regarding the wearing of helmets, and why the campaign for wearing it is
presently itensified.
According to this theory, the too early introduction of a law would
provoke too much resistance. A 7-year strategic approach is suggested.
The first 3 years will win the innovators, the precocious adoptors and
the precocious majority, thus about 40% to 50% of the population. Then,
law support will be unfold, giving a fast raise - in about a year - in
order to reach about 80% of the population. Coercive measures will
then unfold on the next three years, to reach about 90% to 95% of the
targeted crowd. (2)
We feel as much empathy from this as from a bulldozer!
Less cyclists, less injuries
Upon hearing people who oppose the mandatory wearing of the helmet - let's
call them the pro-choice from then on - we see that their arguments are
far from originating from people who are "inferior on the socio-economic
plane, less educated, living in the past". Serious motives justifies such
a position.
The biggest concern of the pro-choice people is founded on the case of
the state of Victoria in Australia, state who passed on a mandatory helmet
law in 1990. High success rate: according to the Transport Accident
Commission, head injuries dropped by 63% while general injuries dropped by
21%. Another statistical source, the Victorian Injury Surveillance
System, puts the drop of head injuries dwon to 32% for children and 21%
for other injuries. A third source, the State Health Department, who is
compiling the stats regarding the hospital cases, shows a drop of 47%
regarding cyclists with head injuries, and 30% for other injuries (3).
But wait a minute! How can we explain the drop of injuries not related to
the head? The Monash Research Center on Accidents in Melbourne revealed
that there was an actual drop in cycle use after the passing of the
mandatory helmet law: 36% less children were cycling and 44% less
teenagers in the 12-17 years old bracket (4). That explains the high
success rate of the law. Less cyclists, less injuries!
In fact, and we'll come to that later, we can even expect a drop in public
health and urban environment if there are less cyclists around.
Following the angle
Dussault, of the SAAQ, gives us more revealing statistics. "During the
last decade (1981-90), there was an average of 36 deaths, 330 serious
injuries, and 3,400 light injuries for a total of 3,766 yearly cyclist
victims injured in an accident involving a motor vehicle (AVM). If we
consider the under-evaluation of AVM accidents (about only 35% of these
are officially declared) and the victims of accidents not involving a motor
vehicle, the number of cyclists victims would rather be in the 10,000 per
year, including about 40 deaths. According to Statistic Canada we can
estimate the cyclist crowd in Quebec (of all levels) to about 3 million
people. This lets us deduce very approximative rates of 0.13 deaths and
33.2 injuries per 10,000 cyclists. These rates are much better than the
ones for passengers of motor vehicles who were, in 1990, of 2.38 deaths
and 125.2 injuries per 10,000 motor vehicles in circulation" (5).
It is when Dussault translates these figures in _risk per traveled
kilometer_, the distance traveled yearly by a cyclist - about 800 km per
year - being, according to him, 20 times less than motor vehicles (16,000
km per year, average) that he concludes that "the bicycle is a means of
transportation which, per traveled kilometer, is more risky than motor
vehicles" (6). That we can consider, per packs of 10,000 cyclists, per
traveled kilometers, per hours spent in traveling, per dollars saved, per
burned calories, per happiness felt, is utterly a fantasy lending itself
to a compulsive use of numbers.
Dussault adds: "Notwithstanding a higher rate of accidents per traveled
kilometer, we notice a proportional limited number of injured cyclists
for a very large number of users. But then, such a large group of
cyclists (the estimated 3 million people) would call for major investments
that the absolute number of victims would justified with strong
difficulty when regarding the overall state of road final report
[i.e. a large group might justify major investment in roadway infrastructure,
but the small number of victims would not.]
In absolute numbers, in fact, we see that in 1991:
- 38 deaths and 422 seriously injured when riding a bike;
- 586 deaths and 4,083 seriously injured while riding a car;
- 146 deaths and 866 seriously injured while walking (presumably by motor
vehicles.) (7)
Why are we imposing the wearing of the helmet to the smaller group when
there are much more savings in health care to be done with the other 5,220
victims of deathly or serious accidents in the two other groups? The
helmet would cause much less hassle wore [when worn] by car drivers
who wouldn't be affected by heat and ventilation problems and who would leisurely
leave the helmet in their cars upon arrival at destination. Incidently, along
with the TV adverts for the helmet ("Have you fell on your head?") the
SAAQ is also broadcasting "Speed Kills" adverts in which a young woman is
killed, being a passenger is her boyfriend's car. Have you notice that
she died because her head hit the metal border of the windshield? The
SAAQ is clearly showing here two weights, two measures.
Otherwise, it was computed - since public funds is a major concern in
this security campaign - that the promotion of the helmet in the state of
Victoria in Australia in 1984, more than $565,000 Australian currency,
made the followings security gains: 43 less cranial traumatisms, hence a
direct savings of $13,000 for each missed injury (8).
There are injuries and injuries
Another to-the-point study by the SAAQ shows the following places of body
injuries in percentage, for _all_ types of road vehicles:
- 34.1% inferior [lower] part of the body
- 27.1% head and face
- 19.3% superior [upper] part of the body
- 11.4% trunk(9)
So, should we first protect the legs?
More specific, the head and face injuries are divided along these lines:
- 33.3% amongst the rear passengers of cars and taxis
- 29.8% amongst passengers of trucks and semis.
- 29.0% amongst truckers (drivers)
- 27.1% amongst cyclists
- 24.5% amongst drivers of cars and taxis
- 23.2% amongst front passengers of cars and taxis
- 21.6% amongst pedestrians (10)
Here, we find that it is the rear passengers of cars and truckers that
would call for immediate attention of road security managers.
But when we look at the specifics of cerebral-cranial traumatisms we
learn that the "passengers of this group is over represented for this type
of injuries", as:
- 59.0% amongst the global occupancy of these vehicles, including 39.4%
for drivers alone
- 17.2% amongst pedestrians
- 7.7% amongst cyclists
- 6.7 % amongst motorbike drivers (11)
Amongst cyclists, 53% of head and face injuries are in fact wounds
without any fractures or internal traumatisms (12). It is well known that
the seriousness of injuries is a function of the kinetic movement (speed)
of vehicles involved; the low speed of bicycles takes them out of this
picture. The 1991 road final report attests to this fact. While cyclists
were reaping 7.8% of all road accidents, they only got 3.7% of deaths
and 5.9% of the ones including serious injuries, with 8.2% of light
njuries (13): many minor accidents, not many fatal ones.
As a conclusion, the authors of this exhaustive study underlines that
"the victims with the most serious accidents are found amongst the
occupants of cars and taxis, pedestrians, and motorcyclists [...]; the
victims with cranio-cerebral traumatisms are found more likely amongst the
occupants of cars and taxis than amongst pedestrians;" the study thus
recommends the use of inflatable cushions and seat belts. The same
authors didn't find any serious problems amongst cyclists, nor they did
made any recommendation for them.
"Survival Ability" with or without helmets
Another interesting question: why focus on the protection of the head of
cyclists while there is pratically nothing done for the integrity of
their bodies? The head is the depository of vital functions and universal
conscience, but a body in pieces is nonetheless not an enviable state. A
recent study of the British Medical Association, debates the question
under this angle (14). It reports that according to the British Transport
Department, 95% of deaths and 90% of serious injuries occuring on a bike
includes a motor vehicle. According to this report, the helmet wouldn't
prevent two thirds of these fatal injuries, cyclists then dying of
injuries to other parts of their bodies.
Same report underlines that the conclusions of the helmet promoters are
based on very local facts, a narrow range of sampling, from which only
limited conclusions can be drawn. The fact is, no-one really knows if
the wearing of a helmet actually reduces the seriousness of accidents and
in which extent; this eventuality is only hypothetical at the moment.
Helmet or safety?
Hence, we don't know if the drop in serious head injuries amongst cyclists
is due to the wearing of the helmet or to safety habits. Velo Quebec
offers some data that supports this observation. After observing 19,239
cyclists during the summer of 1991, Velo Quebec reports that "cyclists
respecting the traffic lights wore a helmet in 81% of the cases, while
71.8 % of cyclists also respecting traffic lights didn't have a helmet
[...] The bikes of 'helmeted' cyclists are more often equipped with the
mandatory reflectors (51.6%) while 40.3% bikes of 'non-helmeted'
cyclists had them [...] Helmeted cyclists respected the flow of traffic in
98.6% of the observed cases while the percentage of respect with
non-helmeted cyclists is 96.8%. " (15)
Kamikaze Helmet?
Nevertheless, even if the helmet is linked to better safety amongst the
portion of the population who is actually wearing it, it is far from clear
if the helmet, once legally imposed, will produce the same results with
the rest of the population. We can actually fear an adverse reaction. We
may as well see less head injuries but a rise of injuries to other parts
of the body, injuries that can very well be as serious.
On this subject, we can draw a parallel with the wearing of helmets in
amateur hockey games. During the 1970s, the helmet became mandatory in
amateur hockey games. While no report of major injuries to the spine was
reported in the midst of the seventies (2 cases before 1976) we found 12
cases between 1976 and 1979, 7 cases in 1980, 12 cases in 1981, 14 cases
in 1982, 16 cases in 1983, and 15 in 1985. Interviewed, the young victims
said that they felt a feeling of invulnerability when wearing their
protective gear (16). This phenomenon, called 'risk homeostasis'
is well-known: the users tend to compensate a security measure by
augmenting their performance or by taking new risks. Thus, the driver of
a car equipped with gripping crampoon tires will have a tendency of
driving faster in the snow, voiding the security gain offered by the
equipment.
We can also fear that the helmet will give rise to more aggressivity from
the car drivers towards the cyclists, due to the drop in number of
cyclists on the roads. This phenomenon is actually observed in Australia
where, taking account of the reduced number of cyclists, the drop in head
injuries cases were less than expected while the injuries to other parts
of the body went up. And cyclists are still dying there, with their
helmet on their heads.
Exaggeration of the dangers of bike riding
We could believe that the recent decline in bike accidents is at the
origin of this sudden rise of helmet promotion at the SAAQ. Not at all.
Velo Quebec signals in fact that "despite the spectacular rise of bicycle
use, the final road report of cyclist-related accidents from the past 30
years are dropping at a nonetheless spectacular rate. While we observed
an average, between 1966 and 1975, of 69 yearly deaths, we see that
between 1982 and 1993 there's an average of 39 deaths (25 in 1992, 23 in
1993), along with a bicycle population of more than three times more"
(17).
This rise of popularity in helmets without any good foundations also bears
another impact: making people believe that bike riding is a dangerous
activity. The British Medical Association is clear on that: "even in the
hostile environment of today's traffic, the beneficial aspects of steady
bike riding exceeds the registered yearly deaths associated with this
activity." According to them, it is in fact more dangerous NOT TO cycle,
for both the cyclist and society in general.
It is extremely delicate to play around with this notion of 'dangerous
bike riding', this notion being the very first reason, and purely
instinctive, put forward by many people refusing to ride on a bike. The
authorities should disarm these fears instead of promoting them.
Without being cynical, it's far more important to put the cyclists on
their saddles than to diminish bike accidents. This because we are, alas,
facing a dilemma otherwise unsolvable: there is a need of seeing more
cyclists in the streets so that the authorities will be pressed in making
safety arrangements.
In Europe, in the countries where we see the biggest number of bikes, the
helmet is virtually absent from the scenery. It is the large number of
cyclists on the roads that provides the security factor. Biking is a
normal, daily, activity, and we shouldn't do it dressed in middle-ages
armors.
References used in this article
(1) Claude Dussault, coordinator, planification [planning] and development, for the
Quebec Automobile Insurance Society (SAAQ), , Perspective mondiales sur le velo, Conference
velo-mondiale, Velo Quebec, Montreal, 1992
[the SAAQ is the government-owned motor vehicle insuring agency in
the province of Quebec]
(2) Idem
(3) Max Cameron and Lorna Heimann, Monash University, , Perspectives
mondiales sur le velo, Conference velo-mondiale, Velo Quebec,
Montreal, 1992
(4) Idem
(5) Claude Dussault, coordinator, planification and development, for the
Quebec Automobile Insurance Society (SAAQ), , Perspective mondiales sur le velo,
Conference velo-mondiale, Velo Quebec, Montreal, 1992
(6) Idem
(7) SAAQ, Bilan 1991
(8) Jean-Rene Carre, , Perspective mondiales sur le velo,
Conference velo-mondiale, Velo Quebec, Montreal, 1992
(9) Louise Charron et Rbah Saighi, Profil des blessures des victimes
d'accidents de la route, SAAQ, February 1992
(10) Idem
(11) Idem
(12) Idem
(13) SAAQ, Bilan 1991
(14) British Medical Association, Cycling Towards Health and Safety,
Oxford University Press, 1992
(15) Laurent Moreau and Jean-Francois Pronovost, , Perspective mondiales sur
le velo, Conference velo-mondiale, Velo Quebec, Montreal, 1992
(16) Charles Tator, , Clinics in sport medecine,
Vol. 6, No. 1, January 1987
(17) Jean-Francois Pronovost, ,
Info Velo Quebec, Vol 1, No 2, May 1994
[notes in [ ..... ] added for clarity]
This article was originally published in Le Monde a Bicyclette, Vol. XIX, No. 2,
Summer 1994