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

Return to: Home