Accidental road traffic deaths—Prospects for local prevention

AC&. Awl. ancfPrev. Vol. 26, No. I, pp. l-9, 1994 Printed in the U.S.A.

ACCIDENTAL ROAD TRAFFIC DEATHS-PROSPECTS FOR LOCAL PREVENTION JEN~ STEENSBERC Institution

of Public Health Medical Officers, DK-3400 Hiller@d, Denmark

A.bsfracf--One hundred sixty-three fatal road traffic accidents (RTAs) resulting in 178 deaths occurring from 1’683-1987 in a Danish county have been studied from a preventive perspective. Alcohol was an important factor in 41% of all fatal RTAs. Other factors such as high speed, the use of seat belts and helmets, and tt,chnical defects are mentioned. Also, the material has been analyzed according to types of accidents. Prospects for the local prevention of RTAs are discussed with particular emphasis on accidents related to alcohol and high speed. Examples are given of preventive activities where experience gained through the p-esent study have been useful.

In Dertmark, from the late 1960s the number of deaths from road traffic accidents has been decreasing. Ir Frederiksborg County, located in North Zealanj (north of Copenhagen), with a population of app~ximately 340,000, the accident pattern is generally comparable to the situation in the rest of the country. The annual number of accidental deaths amoun’:s to 3 per 10,000 inhabitants; one of these deaths is caused by a traffic accident. Local accident data are of special importance as a motivating factor for local preventive action. The amhor, in his capacity as regional public health medical officer (PHMO) advising local authorities on environmental health questions, therefore decided to study available material illustrating the regional pattern of accidental death. A better understanding of the causal web behind these accidents should improve the possibilities for preventive action. The present paper describes the pattern of fatal road traffic accidents (RTAs) in this Danish county and discusses prospects for local preventive activitiesI .

MATERIAL

AND METHOD

To get a sufficient number of cases a five-year period, 1983-1987, was chosen. As the study was initiated early in 1989, it could be expected that the administrative and legal handling of cases from the last year, 2987, were finished and experience from the first years would still be relevant. The starting point was records, belonging to the Institution of PHMOs, of the medico-legal inspec-

tion of corpses. This is in Denmark performed by PHMOs in cooperation with the police. On the ba: I s of a written police report on ihe circumstances WI-rounding a fatal accident, it is decided whether a postmortem examination at the Institute of Forens c Medicine in Copenhagen is needed. The PHMO fil Is in the death certificate. The official definition of an RTA, i.e. an act dent on a public road, where at least one of tl+c traffic elements was driving, has been followed. A II such accidents that had taken place in the count:~ were included. Obvious cases of suicide, e.g. a frori tal collision with a truck and a history of depressio:t and suicidal threats, or natural death were systemat itally excluded. The medico-statistical department of the N*Itional Board of Health supplied routine mortalit ‘1 data from its death register and copies of all deal 11 certificates from the study period that had bee11 coded as road traffic death. It was expected that thi: total number might be slightly higher than the polic I: figures, as police-based statistics do not count deatt^ i later than 30 days after the accident. However, i t this study the corrected figure of I78 deaths corre:,ponded with the NationaI Board of Health numb< . of 183 after the exclusion of five suicides. Danmarks Statistik, with the permission of thl.! Ministry of Justice, supplied a list of case recor:l numbers of police reports on fatal RTAs. The Mini? . try also permitted the author to examine all files OII RTAs causing death in the three police districts c“ the County. Due to the small quantity of the materi21 R computerization of the data was not considerel,! relevant.

2

J. STEENSBERG

A survey form was developed to be used when extracting information from police records, etc. Particular emphasis, from a preventive perspective, was given to factors that might have been influencing the occurrence-e.g. locality (weather, lighting, road character, speed limits, etc.), elements (vehicles, obstacles, manoeuvring, speed, etc.) and personal circumstances (driving licence, intake of alcohol/ drugs, illness, use of belt/helmet, suspected suicide, etc.). Preliminary conclusions on the survey form were grouped in the matrix: pre-event-eventpostevent versus man-vehicle-environment. Also, thought was given to preventive actions aimed at physical, environmental, and human factors and possible barriers to implementation. The time-consuming operation of going through the police material was performed during the summer of 1989. Five police accident reports from 1983 could not be retrieved, but some information exists on the deceased. The case material may have been destroyed probably because it was of no particular interest to the police. Police data supplemented PHMO information in the Institution, especially results of testing for alcohol and drugs, technical reports on car defects, photos, details on circumstances obtained after the medico-legal examination, and any legal sanctions. Through the three different sources of data it could be ensured that all cases were found. The analysis of the material was especially oriented towards evaluating the interrelatedness of factors and the qualitative details of individual cases that are not generally uncovered by the central statistical treatment of police registered data. Certain facts concerning the deceased persons were described, e.g. their traffic role, type of lesion, time from accident to death, influence of alcohol/drugs, etc. Also described were specific types of accidents involving trucks, motorcycles, mopeds, bicyclists, pedestrians, young persons and elderly drivers. Finally, factors related to single accidents, accidents on icy/snowy roads, and occupational accidents were described. Preliminary results including nontraffic accidental deaths were presented at the First World Conference on Accident and Injury Prevention in Stockholm, September 1989. RESULTS According to the official police-based statistics for the period 1983-1987, 189 persons in Frederiksborg County died as a result of RTAs; 2,281 were severely and 1,564 slightly injured (Danmarks Statistik, annual publication). The corrected figure

Table

I. Accidental

Age in years - 14 15-24 25-34 35-44 45-54 55-64 65-74 75Total (%)

road

traffic deaths, 1983-1987

Male 11 42 15 IO 14 13 9 12 126 (71)

Frederiksborg

Female 7 14 0 8 7 3 4 9 &

County

Total 18 56 15 18 21 16 13 21 178 (100)

for deaths according to this study was 178 resulting from 163 accidents. Table 1 shows the distribution of the 178 deaths according to sex and age. According to experience from casualty departments on defects in police registration (Ulykkesanalysegruppen 1986), the number of severely injured for the five-year period would rather have been approximately 2,700 and the number of slightly injured approximately 4,500. This means that, generally speaking, for each person killed in a traffic accident 1.5 were severely wounded and 25 received lighter injuries. The lower death figures for women are related to the fact that they drive less than men, i.e. women account for only 25% of the total “traffic activity” (Radet for Trafiksikkerhedsforskning 1989). Figure 1 relates the absolute numbers to the population. For younger people the trend is parallel to that for all accidental road traffic injuries. However, amongst the elderly the death rate is considerably higher than would be expected from the number of injured. Most people who are killed in RTAs die immediately or within a few minutes. This was the case for 106 persons (60%). 72 reached the casualty department or were in a hospital ward before they died. One hundred thirty-two (74%) of all deaths occurred within the first 24 hours. The majority (74%) of the fatally injured persons had received head injuries. A full postmortem examination by an expert in forensic medicine was performed on 107 (60%) corpses to clarify the character and development of lesions. Only four persons were shown to have been under the influence of drugs or narcotics that might have been of importance to the development of the accident or the fatal outcome. In 11 persons manifest somatic disease was relevant as a causal factor or for the mortal effect. Deaths that had already been registered on the death certificate as suicide or natural death were not included in this study. A further five deaths related

Local prevention of accidental road traffic deaths

Male

* -

3

-

Female

01 Age and sex distribution of population 1. jan 1985. Fig. 1. Frequency

of accidental road traffic deaths. Frederiksborg

to traffic situations that, considering all available evidence, were seen as obvious suicides were also excluded, but a suspicion of suicide still existed for eight nen and one woman. This does not include the self-destructive behaviour that is characteristic of sej,eral male traffic fatalities, especially when driving under the influence of alcohol. Tible 2 shows the traffic role, sex, and age

Table 2. TrafEc role, sex, and age in accidental road traffic deaths, Frederiksborg County 1983-1987 Traffic ule _~ Car dri\Ier Front Seat passenger Back seat passenger Car passenger unspecified Motorc Jcle driver MotorcJcle passenger Moped driver Moped passenger Cyclist Pedestrian Other Total

Male 48 16 4 1 I1 0 14 1 13 1.5 3 126

County 1983-1987.

of the dead persons. Of the 42 young men ag,:d 15-24 (Table l), 25 were killed in car acciden:.s, 9 as motorcycle drivers, 7 driving mopeds, altd one as a pedestrian. Among the 21 persons ag’.:d 75 and over 12 were killed as pedestrians. Mclst of the 18 children were on bicycle (8) or on fci Jt (5). The following sections describe the results Jf the analysis of the 163 fatal RTAs. A more detailI:d account of the study has been given elsewhc -e (Steensberg 1991).

Female

1

62 24 8 2 I1 1 15 I 19 31 4

52

178

14 8

4 1 0

:, 6

16

The influence of alcohol was an important fact ‘.)r in 66 (40.5%) of all RTAs. This means that a pers+‘,n acting in a traffic situation so that he/she must te judged to be carrying the main responsibility for t fe accident had a measurable level of alcohol in t e blood. In the opinion of the author, the course N,)f events in these cases shows that in 56 (85%) of theb$,,e cases alcohol intoxication was the most important factor. In other words, if this person had not been under the influence, the accident presumably wou Id not have happened. Only 3 intoxicated women vc r-

4

J.

STEENSBERG

Table 3. Blood alcohol concentration in persons with main responsibility for alcohol-related fatal road traffic accidents, Frederiksborg County 1983-1987

Table 4. Cofactors in 66 fatal road traffic accidents with measurable blood alcohol in the person carrying the main responsibility, Frederiksborg County 1983-1987

Alcohol concentration in blood % (g/l)

Cofactors

0.3-0.4 OS-O.7 0.8-1.1 1.2-1.5 1.6-1.9 2.0“Intoxicated”*

Wood

Male

Female

2 6 7 13 14 18 3

0 0

2 6

1

8

0 0 0 2

13 14 18 5

63

3

66

alcohol concentration

Total

judged to be at least 0.8%~.

sus 63 men carried the main responsibility for such accidents. The dominant group was young men aged 15-25 (25 in all). In only two cases the counterpart to the person with main responsibility also had alcohol in the blood (0.4 and OS%, (g/l)). In both cases this was considered of no importance for the course of events, Table 3 shows the blood alcohol concentration in persons with main responsibility for alcohol related fatal RTAs. In 58 of the mainly responsible persons the blood alcohol concentration was at least 0.8%0 which is the legal limit in Denmark. In male intoxicated car drivers, the blood alcohol concentration was generally higher in the age group 25-64 than in the young. More than half of the intoxicated 25 to 64-year-old men were judged to have a real alcohol problem, i.e. a large daily consumption or a recent history of treatment (failures). This study has not brought forward other factors that might explain why these men, who probably frequently drive under the influence, were involved in these particular accidents. Four adult men (above 24 years of age) may be suspected of suicide and another four showed typical self-destructive behaviour. Table 4 gives a list of cofactors in cases with alcohol intoxicated persons carrying the main responsibility. It can be seen that the high speed of the vehicie driven by the intoxicated person was an important contributory factor. However, especially in single accidents, i.e. involving only the vehicle driven by the deceased person, speed could frequently not be judged. Difficult lighting conditions do not cover all cases occurring during the dark hours, difficult road conditions do not include many normally occurring circumstances that present particular difficulties to an intoxicated driver, and vehicle defects were in no case of decisive importance.

Speed of vehicle driven by the intoxicated person High speed of considerable importance High speed of some importance High speed of no importance Normal speed No information Difficult lighting conditions Dif~cult weather conditions Difficult road conditions Vehicle defects Suspicion of suicide Fatigue Benzodiazepine in blood Disease Conduct of other person

Number of cases 30 8 5 14 9 26 14 6 14 6 2 2 1 3

Speed The importance of high speed as a causal factor for fatal RTAs is generally underrated as enough information is lacking in a number of cases. In 70 (43%) of all 163 accidents sufficiently detailed data were available to allow the judgement that excessively high speed according to circumstances and/or exceeding existing speed limits was of importance. The analysis leads to the conclusion that approximately 90% of motor vehicle drivers who were driving too fast carried the main responsibility for the accident. It may be difficult to judge the causal importance of high speed in individual cases compared with other factors. When cases with alcohol intoxication and suspicion of suicide are excluded (these factors then being considered more important than speed), high speed is judged to have been the main cause in 39% of the 70 RTAs where high speed was a known factor. Other fuctors Information on the use of seat belts in RTAs where the deceased person was in a car was available in only 72% of cases. Several police reports did not register this fact and later technical investigations did not allow a firm conclusion. In a considerable number of accidents with no information-especially single accidents and cases of drunk driving-circumstances led to the assumption that belts had not been used. In cases with sufficient information 71% of drivers or passengers did not use a seat belt. Circumstances of the accidents showed that more than half of unbelted drivers and passengers who were killed in cars would presumably have survived if they had been wearing a belt.

5

Local prevention of accidental road traffic deaths

Most of the killed motorcycle/moped drivers or passengers were using a helmet. No bicyclist was wearing a helmet, which would at that time have been very unusual, but it is judged that for approximate y one-third of the 19 killed bicyclists a helmet migh. have prevented the fatal outcome. In only five of approximately 190 inspected cars did technical defects play a major causative role. In a further 11 cars such defects may have acted as a contributory factor. Technical faults of some sort were found in 15% of inspected cars. The use of headlights in daytime-which was not yet mandatory during the studied period-might have had preventive importance in 17 RTAs.

Type>, of accidents In around half of the 29 fatal truck accidents the driver was judged not to be responsible for what happened. Where the truck driver had the main responsibility he was frequently alcohol intoxicated and/or driving too fast. Also, problems with the braking system sometimes played a part. In far the majority of motorcycle accidents the drivel, carried the main responsibility. Usually the accident happened at very high speed and half of the responsible drivers were under the influence of alcohol. Moped accidents resulted in 15 deaths. Most of the young drivers (1.5-21 years) who were killed were themselves responsible through their conduct. C’hildren and elderly people on bicycles usually, as a result of their behaviour in the traffic, were themselves the cause of the fatal accident. The typical situation was an abrupt turn to the left to cross the road or neglecting the right of way of traffic on major roads when entering from a side road. Circumstances around fatal RTAs involving pedestrians indicate that children up to the age of 11 suddeinly and inattentively may cross even roads with heavy traffic. Old and especially senile persons likewise quite unexpectedly may cross the road. Adult men with alcohol problems are problematic both in traffic and as pedestrians. In most RTAs involving persons on foot that occurred in darkness reflective material on clothes might have had preventive importance. Fifty-six young people (15-24 years) were killed in RTAs in Frederiksborg County during these five years. Twenty-three young men were intoxicated while also carrying the main responsibility. In accidents with young male car drivers, high speed was a particularly frequent causal factor. Also, victims in cases involving fast driving were generally young people. Close to three-fourths of young male car

drivers involved in fatal RTAs were judged to hi tve the main responsibility. The most typical traffic violation in older l:ar drivers (65 years and older) was not paying attent on to the right of way of other traffic when enter ‘ng major roads. Illness was of major causal importance in 011ly 13 cases, but impaired health for some persons was of significance for the fatal outcome. DISCUSSION AND PROSPECTS LOCAL PREVENTION

FOR

General During the 1970s the British Transport and Rc lad Research Laboratory performed thorough studiec’ of approximately 2,000 road-traffic accidents (Gri Ine 1987). The investigation team attempted to estimicte the percentages of RTAs that could be attribu’ed to defects in or defective performance of the r( ad environment, the vehicle, or the road user, and to study their interaction. Human factors were judrd to have been present in about 95% of the accideslts and to have been the sole contributor in about 65’ G. The road environment was present as a factor in about 28%, but as the sole factor in only 2%. l’le vehicle played a part in about 9% of RTAs, but 01Ily in approximately 2% as a single factor. In around one-fourth of all cases the main explanation was to be found in the interaction between road user alld road environment. In the present study expressions like “mair ly responsible” and “main cause” have been uscmd. Designers of studies of injury events may be temptl.:d to require that a single factor be designated as the cause or as the primary cause of the event. Wal :r (1987), however, warns the researcher that tryi,lg to designate only one as the (primary) factor oftl.:n becomes an arbitrary task in which the designati,,ln usually is determined by prior conceptual biasess. Yet, the analysis of accident circumstances in tl le present study, seen in a practical preventive pei-spective, frequently pointed to one or two facto1 s of paramount importance. It was also usually e\ ident who among the involved persons must lie judged to carry the main responsibility for what ha Ipened. With the risk of oversimplification such o Iservations may be important when considering pr, ventive strategies. It has, thus, been difficult to systematize sevet (11 variable conditions related to the road environme ,lt such as the state of the road, visibility, lighting, and weather. However, these factors have been tak(*n into consideration in the individual cases when jud:.:ing responsibility. They may be especially important as contributory factors when the driver is intolr,i-

6

J. STEENSBERG

cated or driving too fast. A study of this character also does not give due credit to the importance of the road engineers’ efforts in improving the permanent road environment. Fatigue as an accident-provoking factor is difficult to get at. It is an often overlooked cause but may give an obvious explanation to some otherwise unexplainable accidents, especially at nighttime (Corfitsen 1986). Maybe most accidents involving sober drivers at night can at least partly be explained by fatigue. This study does not give an impression of the effectiveness of the ambulance services. Also, the efforts in the casualty department and the long-term treatment of the patient cannot be judged. Only in a few concrete cases is it evident that more effective first aid might have been life saving and that a different choice of treatment could have resulted in possible survival. Disease prevention is a more difficult enterprise than one might think (Steensberg 1989). It is not only a question of persuading individuals to change lifestyle, but also to motivate organized society to give preventive measures a reasonable priority. Historical experience shows that public health problems cannot be solved by focusing on individual behaviour; they are essentially social in character and must be solved primarily by changes in the environment and in terms of social policy. Individual behaviour is conditioned by past history and by the economic, social, and political structure of society. If we are to succeed in making even modest changes in the lifestyles of our populations, a major pedagogical task lies in front of us. The results of preventive action usually are long term and uncertain, but the prevention of RTAs often leads to more immediate and tangible effects. In Denmark, the Traffic Safety Commission in 1988 published its epoch-making action plan with precise goals for traffic safety activities until the year 2000 (Fardselssikkerhedskommissionen 1988). If these proposals were followed, it should be possible to reduce the number of traffic deaths and casualties by a further 40%-50%. In 1989, Frederiksborg County, in cooperation with the National Traffic Safety Council, established a three-year demonstration project. This was a follow-up of the part of the Traffic Safety Commission’s plan that deals with local preventive activities, including education, information, and campaigns. The author took part in this project during the years 1990-1992, when experience gained through the present study was most useful. Some examples of activities will be mentioned below. During the first part of the project an informa-

tion group representing journalism, traffic safety planning, police, and public health was actively running an information series in the regional daily newspaper and local weekly papers. Individual cases and the general knowledge on accident mechanisms gained through this study were used in formulating contributions. Inspired by the principles used in the present study a multidisciplinary accident investigation group began analysing all fatal RTAs in 1991 and is continuing its work. Experience of this group has stimulated information activities aimed at the public and adjusted priorities in regional traffic safety work. Conclusions and recommendations in the report for 1991 have been widely quoted in local and national media (Frederiksborg Amt April 1992). As an example of derived actions, the author has reminded medical doctors working in the county of their legal obligation to prevent old people and persons with certain diseases who may represent a hazard to themselves and others from driving motor vehicles. One of the county municipalities, Frederikssund, a town of approximately 17,000 inhabitants, has from 1990 participated in a Danish Five-City Accident Prevention programme based on local hospital registration of outpatients. The author has been analysing local data on RTAs based on experience from the present study while chairing a multidisciplinary traffic safety group as part of the project. Several information activities including some on RTAs have taken place with some support by the county project and national campaigns.

Alcohol

and drugs

An extensive Danish roadside survey performed from 1985-1987 has shown that .48% of the men’s driving is carried out with illegal breath alcohol concentrations whereas women’s illegal driving amounts to only .04% (Radet for Trafiksikkerhedsforskning 1989). On weekend nights and Friday evenings well over 1% of the traffic is controlled by drivers with illegal breath alcohol values. In the present study alcohol intoxication was an important factor behind 41% of fatal RTAs. This compares with results from the western part of Denmark in 1976 where 36% of fatal RTAs involved alcohol (Schnedler et al. 1983). In both studies onehalf of the motorcyclists were killed in an alcohol accident. Almost half of young (18-24 years) male car drivers in Frederiksborg County who carried the main responsibility for a fatal RTA were alcohol intoxicated. Dalgaard (1977) found that close to half of all drivers causing a fatal accident in a car (who were tested) had alcohol in the blood. In his opinion

Locai prevention of accidental road traflic deaths

a blood alcohol level of 1.5%0 or more is suggestive of chronic alcoholism. In this study signs of the influence of drugs or narcotics were found in only four deaths. However, the police do not in all cases request an analysis for, e.g. psychotropic drugs. Drivers taking minor tranquillizers are at increased risk of having an RTA (Skegg et al. 1979). In a Danish study performed in 1983, 15% of alcohol-negative blood samples were found to be benzodiazepine-positive (Worm et al. 1991). It is difficult to distinguish whether the increased risk is due to effects of the drugs themselves or the diseases being treated. Oster et al. (1990), however, doubted that benzodiazepine users basically are more accident prone than nonusers, due to dir’ferences in behaviour, lifestyle, occupation, etc., which suggests that the use of benzodiazepine is the important factor. No doubt, the most important target for information and education to prevent drunk driving is the group of young men-and their girl friends. Danish experience from recent years has shown that accident figures can be inlhtenced by health education activities. In the county of North Jutland (with a population of close to 500,000) campaigns in 1988 and 1989 directed at the 17- to 20-year-olds more than halved alcohol-related RTAs involving young people, during the summer period. However, the effect tends to disappear after some months. The Frederiksborg County Project has from 1990 carried out annual summer campaigns aimed at the age group 17-20. It is difficult to know the effect of specific local actions but the downward trend in drunk driving has been more pronounced in this county than national figures. Based on the present study it is felt that also the mixed group of middle-aged, male “social drinkers” who are not chronic alcoholics may be reached with health information supported by existing regulations and sanctions. Table 5 sums up important elements in the prevention of RTAs related to driving with alcohol in the blood.

High speed is a particularly typical factor in fatal RTAs where young male drivers bear the main responsibility. Young men seem to rate traffic situations as less risky than do older male drivers (Trankle, Glelau, and Metker 1990). Healthy young people have an unrealistic perception of their own vulnerability to hazards (Weinstein 1984). Unrealistic optimism is usually present for events perceived to be controllable. Young persons believe their actions, lifestyle, and personality to be more advantageous

Table 5. Prevention of alcohol-related

7 road traffic accider s

Elements in prevention

-

General More visible police on roads Frequent and random breath testing Young men Campaigns and education directed at young men and the girl friends Social drinkers-mainly men Campaigns directed at persons with a generally positive : ttitude toward traffic measures Information on penalties and sanctions and increasing the ir severity Lowering of the legal limit for alcohol content in blood Alcoholics-mainly men The general alcohol policy of society Changing people’s attitudes toward intervening in drunk driving Treatment of alcoholism as an alternative to punishment

than those of their peers. Persons who engage in high-risk behaviour should see themselves as :he ones most at risk. Despite driving too fast and in an undisciplined manner, poor drivers make trip a”tet trip without mishap. This personal experience #ISsures them of their exceptional skill and secure ty. Moreover, the news media show them that wllen accidents happen, they happen to others (Fischhijff et al. 1981). The relationship between real and perceived’.iifhculties on the road seems to be an important fat OI in governing the behaviour of drivers (Vejdatalaboratoriet 1987). The efforts of road technicians to fac,ilitate the road user’s task may, negatively, lead to an increase in speed and thus in the degree of “d 5 culty” ) or the driver may become apathetic and 1lay less attention to circumstances. The subjectively 1.:xperienced difficulty should not be reduced but rat Iler increased. The introduction of differentiated speed lin !its in towns with lower limits on roads with special safety problems has been estimated by the Traific Safety Commission to represent a profitable invc stment (F2erdsselssikkerhedskommissionen 19813). This has led the Frederikssund traffic safety grttup (Five-City Project), stimulated by case experience from the present study, in cooperation with the SIXretariat of the County Project to put forward a pi an for local differentiated speed limits in the town of Frederikssund. Preliminary reactions, espechl Ily from the local police have, however, been sceptical. Table 6 shows important elements in the prevention of RTAs related to high speed.

8

J.

Table Elements

6. Prevention

of speed-related

road traffic

STEENSBERC

accidents

in prevention

More visible police on roads Automatic speed control Increased severity of sanctions Differentiated speed limits in towns Technical alterations of roads Campaigns directed at men with risky behaviour Driver’s license on trial for young men

Other factors

Seat belts were not used by 71% of car drivers in cases where information was available. This compares with Dalgaard’s (1977) study where 73% of the deceased had not used a belt. This author estimated that more than half of unbelted drivers and passengers killed in a car might have survived if they had used belts. Dalgaard found that 46% of front seat occupants might have survived. Those segments of the driving population who are least likely to comply are precisely those that are at highest risk of serious injury (Waller 1987). Such groups include young males, persons with elevated blood alcohol concentrations, and persons who engage in risky driving. It is certain that seven out of the 11 motorcycle drivers used a helmet. In Nordentoft and Rock’s (1986) study on 300 motorcycle deaths 82% of killed drivers and 69% of passengers were wearing a helmet. Bicycle helmets are very effective in preventing head injuries in biking children (Thompson, Rivara, and Thompson 1989). The incidence of brain and skull injuries is especially high in children and teenagers on bicycle (Nielsen, Larsen, and Nordentoft 1990). In this study it was judged that approximately one-third of bicycle deaths might have been prevented by using a helmet. Test examiners in Dalgaard’s study (1977) made “technical remarks” on well over 20% of inspected vehicles but only in 4% of cases was the defect, judged by the examiner, contributing as a causal factor. In Frederiksborg County 1.5% of inspected cars had some sort of-frequently minor-defect. In the author’s (not the examiner’s) opinion technical faults were either a major or contributory causal factor in 8% of inspected cars. The Frederiksborg County Project has led to changed priorities in road engineering measures: e.g. establishment of speed-reducing “bumps” on roads through villages and information activities to explain the idea behind, for example, new roundabouts. The group investigating fatal RTAs (inspired inter alia by this study) has suggested that the most effective technical measure to reduce serious RTAs in this county may be the systematic use of profiled re-

fleeting lines along road edges (Frederiksborg April 1992).

Amt

Types of accidents

Nordentoft and Rock (1986) suspected that in the majority of fatal motorcycle accidents speed limits had been violated. Where sufficient information was available this was a factor in 70% of cases, which compares well with results of the present small amount of material. The same is true with driving under the influence where 45% of drivers (Rock and Nordentoft 1986) had at least 0.8%0 alcohol in the blood. The average annual distance travelled by an elderly person (aged 65 years and older) by all modes of road transport is only 30%-40% of the average distance travelled by younger adults (25-65 years) (OECD 1986). Yet, the road accident fatality rate is considerably higher for the elderly. Swedish experience has shown that car drivers in the 75 to 84year-old age group are at four to six times greater risk than middle-aged drivers of being involved in RTAs with personal injury (Brorsson 1989). Dutch studies point in the same direction and particularly elderly pedestrians and bicyclists are at greater risk (Wolffelaar 1989). The relative increase in casualties can at least in part be attributed to the increasing physical vulnerability of the elderly. Experience from OECD-countries is that the average elderly accident victim is about three times as likely to die from his injuries as a 25- to 64-year-old casualty. The increased incidence of accidental road traffic deaths especially at age 75 and over (Fig. 1) thus must be explained predominantly by the increased prevalence of age-related changes in the organism and actual disease in older people. It is dangerous to allow senile elderly people, whose eyesight and hearing is frequently also deficient, to move freely in traffic. An old person walking on the road or standing at the kerb, demands increased attention from drivers to the same extent as a child because of the risk of impulsive and unexpected reactions. In Frederiksborg County, 17% of persons killed in RTAs were pedestrians (19% during the period 1986-1990 [Frederiksborg Amt April 19921). Half of those were killed during the dark hours, and more than one-third of deceased pedestrians were aged 70 years or older. Against this background the RTA investigation group initiated a campaign in the autumn of 1991 to encourage old people, e.g. through home visitors and employees of nursing homes, to wear visible clothes and/or reflective material. For several decades the frequency of child traffic deaths in Denmark has been higher than in Swe-

Local prevention of accidental road t&Kc deaths

den and some other European countries. A Copenhagen study from 1975 showed, like the present study, that three-fourths of children killed in RTAs were pedestrians and bicyclists (Bjerrum and Iversen 1979). Usually the child was formally at fault. The most common accident situation for cyclists occu!-red when turning into another road followed by collision with a motor vehicle. Small children up to their first school years are not mentally suited to function in trafic (Herslund 1988). Not until the age of 12 is the average child able to behave rather safely. Training in formal traffic regulations may even have adverse effects if this does not take into consideration the informal rules of tht: game (van Schagen, Brookhuis, and Wierda 1988). It appears that children in families where parents admit engaging in many unsafe behaviours, such as not using seat restraints in motor vehicles, have an increased likelihood of having a traffic accident :Pless, Verreault, and Tenina 1989). Traffic safety is an obligatory subject in Danish schools and local police frequently assist in classes. As part of the Five-City Project, this teaching was further strengthened in Frederikssund through, e.g. bicycle checkups and a special bicycle training rink. The County Project has initiated visits to ninth and tenth grade classes by a nurse from the local casualty department and a police officer. Acknot.,ledgemenrs-The medico-statistical department of the Nation.il Board of Health, the recording clerks of the three police district;, and Danmarks Statistik are thanked for their kind assistance.

REFERENCES Bjerrun,

L.; Iversen,

L. Bplrns faxdselsd@delighed.

Ugcskr Laeger 141: 1791-1797; 197”?. Rrorsson,

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2708;

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