A further evaluation of the motorcycle rider course

0022-4375188 $3.00 + .OO Printed in the USA

lournal of Safety Research, Vol. 19, pp. 187-196, 1988

0 1988 National Safety Council and Pergamon Press plc

A Further Evaluation of the Motorcycle Rider Course Rudolf

G. Mortimer

A more extensive evaluation than previously was made of the Motorcycle Safety Foundation’s Motorcycle Rider Course. A questionnaire survey was completed by 913 persons who had taken the course between 1980 and 1983 in Illinois and by a control group of 500 motorcyclists who had not taken the course. Compared to the control group, those who had taken the course did not have a lower violation rate, a lower accident rate, a lower total cost of damage to accident-involved motorcycles, a significantly lower mean cost of injury treatment per accident, or a lower total cost of injury treatment. Those who had taken the course did have a lower mean cost of damage to the motorcycle per accident, suggesting that they were involved in less severe accidents. They also made more use of prot,ective clothing. About 30% of those who had taken the course did not subsequently drive motorcycles.

In 1984, Mortimer completed an evaluation of the effectiveness of the Motorcycle Safety Foundation’s motorcycle rider course (MRC) for the training of motorcycle riders. Some of the results of that study were similar to those that had been reported by other investigators of motorcycle rider courses in the U.S. (Lakner, 1984; Osga, 1980; Satten, 1980), Canada (Jonah, Dawson, & Bragg, 1982), and England (Raymond & Tatum, 1977). One of the findings of Lakner was that motorcycle riders who had taken the course had a lower accident rate than a conRudolf G. Mortimer is professor of safety and accident prevention, Department of Health and Safety Studies, University of Illinois, Champaign-Urbana. The author wishes to acknowledge Preston Staley’s substantial assistance with data reduction and analysis.

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trol group of riders who had not - a major difference between that study and the others. Most recently, in a study in New York State (Buchanan, 1987) 26,000 motorcycle license applicants were randomly assigned to one of four licensing/training schemesone of which was the MRC. No significant differences in crash rates were found among the four groups for up to 24 months after licensing. The major findings of Mortimer’s 1984 evaluation were that (a) riders who took the course did not have a lower accident rate than a control group, (b) there were no differences in the violation rates of the two groups, (c) the cost of damage to the motorcycles per million miles (l-6 million km) was not less for those who took the course, (d)

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the estimated cost of medical treatment for injuries per million miles was not significantly less for the group that took the course, (e) the mean cost of damage to the motorcycles was less for those who took the course, and (f) the mean medical cost per accident was also less among those who took the course. The study was done using a total sample of 516 persons, some of whom had taken the MRC within the 3 years prior to the study and others who had not taken the course. The data were collected by means of a 22item questionnaire which elicited information about riding exposure, violations, and accidents in order to evaluate the effectiveness of the course. In order to further evaluate the MRC and to substantiate the findings of the initial study, a subsequent study was conducted in the fall of 1984 using a much larger sample. The results of that study are reported in this paper. METHOD

The same 22-item questionnaire that was used in the earlier study was mailed to a sample of persons who had taken the MRC during 198083. Approximately an equal number of persons were randomly selected from each of the years. About 7% of those in the sample were female, because about 7% of the motorcycle drivers in the state of Illinois are female. A total of 2,307 questionnaires were mailed to persons who had taken the course. If an individual did not respond to the first mailing within 2 weeks, a second questionnaire was sent. Ultimately, 1,298 questionnaires were returned by persons who had taken the MRC - a return rate of 56%. It was subsequently learned that 385 of those who returned questionnaires had reported not driving any miles on a motorcycle during the previous 12 months. Because the questionnaire items all pertained to motorcycle operation in the 12 months preceding receipt of the questionnaire, these 385 individuals were eliminated from the analyses. Nevertheless, it should be noted that these results indicate that about 30% of persons who take the MRC may not ride a motorcycle thereafter. 188

The persons in the control group were motorcycle drivers who had not taken the MRC. This group consisted of persons who entered various motorcycle dealerships in a number of cities in central Illinois and who were asked to complete the questionnaire if they operated a motorcycle on streets and highways. More than 90% of the individuals who were approached completed the survey and returned it to the researchers before leaving the motorcycle shops. Five hundred fully completed questionnaires were obtained in this way. The final sample thus consisted of 1,413 persons who had driven at least some miles on a motorcycle during the preceding 12 months, 914 (64.6%) of whom had taken the MRC and 500 (35.4%) who had not. RESULTS

Demographic

and Other Variables

Age. The age distributions of the two groups of respondents are shown in Table 1. There were more riders under 22 years of age and more over 40 in the MRC group than in the control group, which had more persons between 22 and 46 years of age. The median ages were, however, similar: 29.2 in the MRC group and 30.0 in the control group. Sex. Approximately 7% of the licensed motorcycle drivers in Illinois are females. In the overall sample of respondents, 8.5%

TABLE 1 PERCENTAGE DISTRIBUTION OF AGE FOR MRC AND CONTROL GROUPS

<21

22-30

31-40

>40

27.6

26.2

17.4

28.8

(L = 500)

13.2

34.4

27.2

25.2

Total

(tj = 1,413)

22.5

29.1

20.9

27.5

Note.

chi

f-w MRC

(n = 913)

Control

square

= 53.6,

df

=3, e < .Ol.

Journal of Safety Research

were female- 10.5% of the MRC group and 4.5% of the control group. License status. There is little difference between the MRC and control groups in the type of license held by the respondents. In the MRC group, 86.4% had a Class M license, 10.6% a Class L license (to operate motorcycles with up to 150 cc engines), and 3.0% had no license to operate a motorcycle. A slightly greater percentage of the control group, 89.8%, possessed a Class M license; 6.8% had a Class L license; and 3.4% had no license. Years licensed. In the MRC group, only 25.4% of the respondents had a motorcycle license for 4 or more years, whereas 71.0% of the control group had a license for that length of time (p < .Ol). As noted above, about 3% of the drivers in each group had no license. Protective clothing. Table 2 shows the percentage distribution of individuals in each group who indicated that they “usually” used various items of protective clothing. The motorcycle drivers in the MRC group tended to wear various types of protective TABLE 2 PERCENT OF MOTORCYCLISTS IN MRC AND CONTROL GROUPS WHO USUALLY USED THE INDICATED PROTECTIVE CLOTHING

Group Protective Clothing

MRC

Helmet

Control

88.8

70.4*

91.0

79.v

Boots

67.1

64.9

Gloves

64.6

55.1*

Long

pants

97.0

86.6*

Long

sleeved

83.3

66.P

Eyeglasses,

goggles,

or

faceshield

*Difference

shirt

or jacket

significant

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clothing more frequently than did those in the control group; and, with the exception of boots, the differences between the groups are all statistically significant. Use of automobile safety belts. At the time that these data were obtained, in the fall of 1984, approximately 14% of the automobile drivers in Illinois used safety belts. In this study, 13.3% of the control group reported that they “always” used safety belts when driving an automobile. A significantly greater percentage of the MRC group, 20.1%) indicated always using safety belts when driving. This greater use of safety belts by persons in the MRC group is also shown by the fact that 49.5% of them reported “hardly or never” using safety belts whereas 62.4% of drivers in the control groups hardly or never used belts. Miles driven. The control group respondents drove motorcycles more than did those in the MRC group. The mean (4,985 [7,976 km]) and median (3,999 [6,398 km]) miles driven by individuals in the control group are substantially greater than the mean (2,690 [4,304 km]) and median (1,245 [1,992 km]) miles driven by those in the MRC group. Furthermore, whereas 53.2% of the control group drove 4,000 or more miles (6,400 km), only 23.2% of the MRC group drove as much. Other mileage comparisons. There was no meaningful difference between the MRC and control groups in the percentage of miles driven on city streets and on rural twolane roads. Both groups drove very few miles on either wet or icy roads. However, 52.6% of the control group drove at least 25% of their miles on limited access highways, whereas only 36.8% of the MRC group drove at least 25% of their miles on such roads. The MRC group also tended to drive a smaller percentage of miles at night: only 19.0% drove at least 25% of their miles at night, whereas 29.4% of the control group drove at least 25% of their miles at night. Motorcycle engine size. The individuals in the control group usually drove motorcycles with larger engines: 42.6 % of them reported 189

driving a motorcycle with at least an 800 cc engine, and 79.9% drove motorcycles with engines of at least 500 cc. In the MRC group, only 18.7% drove motorcycles with at least 800 cc engines, and 50.0 % drove motorcycles with at least 500 cc engines (p< .Ol). Compared to the earlier study, the respondents in this study had a greater tendency to drive larger motorcycles. In the earlier study, only 35% of the MRC group and 65% of the control group drove motorcycles that had at least 500 cc engines. This confirms the trend among motorcyclists to purchase larger machines in recent years. Violations Number of moving violations. During the 12 months prior to answering the questionnaire, 5.0% (46) of those in the MRC group and 8.0% (40) of the control group were cited for violations. The MRC group was cited for a total of 60 violations and the control group had 51 violations. The difference between the frequencies of violations was not statistically significant.

Violation rate. The total estimated miles driven by each group was used to calculate the number of violations per million miles. The rate for the MRC group was 24.4 violations per million miles, and that for the control group was 20.5. The difference between the groups’ rates, 3.97, was minor. Regression analysis. Multiple regression analyses were used to determine which variables predicted the number of citations for moving violations. A stepwise regression analysis to predict the number of moving violations was done for both the MRC and control groups. Three variables added significantly to the prediction equation: not wearing a helmet, being younger, and having more accidents reported to the police. These variables only accounted for 9.6% of the variance in predicting the number of violations. Belonging to the MRC or control group was not a significant predictor. 190

Accidents Accident rate. Based on the total miles driven by each group, the accident rates per million miles were 86.7 for the MRC group and 37.7 for the control group. In the earlier study, these rates were 103.5 for the MRC group and 43.8 for the control group. Both groups, and particularly the MRC group, had lower rates in this study. Type of accident. A motorcycle accident is defined as losing control, falling off the motorcycle, or striking an object. Any of these events, no matter how minor and regardless of whether a police report was filed, defines an accident in this study. The frequencies of various types of accidents for each group are shown in Table 3. In both groups, three types of accidentsloss of control, loss of control due to gravel, water, or ice, and collision with another vehicle- made up the majority of the accidents that occurred. These types comprised 89.7% of the MRC group’s accidents and 81.8% of the control group’s accidents. Although there is a general similarity in the types of accidents incurred by the MRC and control groups, there are some differences. Whereas over half (51.6%) of the MRC group’s accidents were due to gravel, water, or ice, only 37.2% of the control group’s accidents were attributable to this cause. On the other hand, a greater percentage of the control group’s accidents involved hitting another vehicle (19.1%) or hitting either a bicycle or pedestrian (8.5%). Regression analysis. A stepwise regression analysis to predict accidents was done for both groups combined. Three variables added significantly to the prediction equation: riding older motorcycles, not wearing a helmet, and having more violations. These variables accounted for 10.3% of the variance in predicting accidents. Belonging to the MRC or control group was not a significant predictor of accidents.’

ITables of intercorrelations tained from the author.

among

variables

can be ob-

]ournal of Safety Research

PERCENTAGE DISTRIBUTION

TABLE 3 OF ACCIDENT TYPES FOR MRC AND CONTROL GROUPS

MRC Type of Accident

(c = 212)

Control (" = 94)

All (fi= 306)

Loss of control

26.9

25.5

26.5

Slid on gravel, water, ice

51.9

37.3

47.4

11.3

19.1

13.7

Rearended by other vehicle

1.9

3.2

2.3

Hit pedestrian, bicycle, or other object

1.4

8.5

3.6

Forced off road

1.9

3.2

2.3

4.7

3.2

4.2

Collision with other vehicle (excludingmotorcycle rearended)

Other (attacked by dog. deer in road. left kickstand dorm, defective front brake)

Age, years licensed, and accident rates. Table 4 shows the effects of age and number of years licensed on the accident rate of each group. Overall, persons over 30 years old and those who were licensed for 4 or more years had lower accident rates than younger persons and those licensed less than 4 years. When controlling for both age and number of years licensed, individuals in the MRC group consistently had higher accident rates than those in the control group, The highest accident rate was that of drivers in the MRC group who were under 30 and had been licensed less than 4 years. These individuals also drove relatively fewer miles. At the opposite extreme, the motorcycle drivers with the lowest accident rate were those in the control group who were over 30 and had been licensed for at least 4 years. They also rode relatively more miles. Age, years licensed, miles driven, and accident rates. In Table 5, which shows the two groups categorized by age, years licensed, and miles driven, the influence of miles driven on accident rate becomes noticeable. Generally, the accident rate decreases quite Winter 19~S~~~ume

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substantially for both groups as miles driven increase. In all but one subgroup (drivers under 30 who have been licensed less than 4 years and have driven over 3,500 miles [5,600 km]), the control group drivers have lower accident rates. Accident rates for drivers licensed 1e.wthan 2 years. Accident rates were calculated for less experienced riders (those licensed less than 2 years) to determine if the course was particularly beneficial in reducing accidents in the beginning years of riding, as might be expected. A comparison by age as well as years licensed could not be done because there were too few drivers in the control group who had been licensed less than 2 years. Table 6 shows the accident rates for the control and MRC drivers who had been licensed 1 year or less and for those who had been licensed 1 to 2 years. The NRC group did not have lower accident rates than the control group in either the first or second year after licensing. Cost of damage to motorcycles in accidents. Table 7 shows the percentage distribution 191

EFFECTS

OF AGE, YEARS

TABLE 4 AND GROUP ON ACCIDENT

LICENSED,

Ag

RATES PER MILLION

30 or hder

MILES

Over Aga 30

4 or More

4 or More

mAccident Nunber Mean

Accident

a .

Hlles

<4 Years

Years

Licensed

Licensed

Licensed

Licensed

167.4

91.5

63.7

42.6

318

144

197

.214

1,860

3,339

1,912

4,387

82.2

48.2

45.7

20.3

75

148

32

212

4,382

4,347

3.420

6,259

rate

Control

Mean

Years

of cases

miles

Nunber

<4 Years

driven

per persona

rate of cases

miles

driven

driven

year

per

prior

persona

to canpleting

questionnaire.

of the costs of damage to motorcycles driven by individuals in the MRC and control groups. About 73% of the accidents of the MRC group and 57% of those of the control group involved damage to the motorcycles of $50 or less, indicating that the majority of accidents were not severe. However, 5.7 % of the MRC group’s accidents and 9.8% of the control group’s involved damage to the motorcycles of more than $1,200, suggesting that the control group’s accidents were more severe. Table 8 shows the total cost, the mean cost per accident, and the cost per million

EFFECTS

OF AGE, YEARS LICENSED, ON ACCIDENT

miles ridden by the two groups. The cost per million miles was not less for the MRC group. However, a t-test on a natural log transform of the cost data showed that the mean cost of damages per accident was significantly less for the MRC group. Again, this suggests that the severity of the MRC group’s accidents was less than that of the control group’s accidents.

Severity of injury in accidents. Table 9 shows the percentage distribution of the basic injury treatments received by drivers in each of the two groups. In the MRC

TABLE 5 GROUP AND MILES DRIVEN IN PRIOR 12 MONTHS RATES PER MILLION MILES


<3D

>30

or Hore

Years

LiCensed

>3,500

Miles

Driven

c3.500

Miles

Driven

>3,500

263

a9

124

60

Control

192

66

74

37

MRC

117

24

78

33

38

76

lb

26.

journal

Miles

Driven

MRC

Control

192

Miles

Driven

4

of Safety Research

Petrucelli, 1984) and of about $18,000 in Louisiana (McSwain et al., 1985). Table 10 shows the estimated total costs, mean costs, and total costs per million miles of injuries to drivers in each of the two groups. Although the total costs per million miles were slightly greater for the MRC group, the mean cost of injuries per accident was lower for the MRC group than for the control group. However, this difference in mean cost was not significant based on a ttest on a natural log transform of the cost data.

TABLE 6 ACCIDENT RATES PER MILLION MILES BY GROUP IN FIRST AND SECOND YEARS AFTER LICENSING

Years

m*ccident Nuaber

rate of cases

Lice.nsed

1 Year

1 to 2

or Less

Years

195.0

126.3

146

220

103.8

72.0

23

47

DISCUSSION

Control Accident Number

rate of cases

The major purposes of this study were to evaluate the effects of the MRC in terms of the extent to which drivers who have taken the course make use of protective clothing, incur violations and accidents, incur damage to their motorcycles in accidents, and incur injury in accidents, when compared with a control group of drivers who have not taken the course. In addition, the study was done to provide a larger data base than an earlier study that used the same procedures and to compare the findings of the two studies. One of the important findings of this study, also reported in the earlier one, is that drivers who took the course used protective clothing significantly more frequently than did drivers in the control group. This is an important potential contribution of the MRC, because use of protective clothing is stressed throughout the course. There was, however, no difference in the frequency with which the MRC and control group

group, 86.6% of those who had accidents had either no or only minor injuries. A greater percentage of the control group drivers had to obtain emergency room and hospital treatment. Estimated cost of injuries. In estimating the cost of the injuries, it was assumed that minor injuries cost $30, emergency room visits cost $4,000, and hospitalization cost $17,000. The estimate of mean emergency room costs is taken from a report of emergency room records in Louisiana (McSwain, Willey, & Janke, 1985). The estimate of mean hospitalization costs is derived from mean reported costs of about $15,000 at three trauma centers in Illinois (Mortimer &

PERCENTAGE

lluber Grolp

MRC

Control

DISTRIBUTION

TABLE 7 OF COSTS OF DAMAGE TO MOTORCYCLES FOR MRC AND CONTROL GROUPS

of

Accidents

0

l- 50

209

41.1

32.1

92

31.5

25.0

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IN ACCIDENTS

51-

101-

301-

1,201-

2,501-

100

300

600

1,200

2.500

4,000

4.3

7.7

3.3

5.7

4.3

1.4

12.0

9.8

6.5

5.4

7.6

2.2

601-

193

TABLE 8 TOTAL COSTS, MEAN COSTS PER ACCIDENT, AND TOTAL COSTS PER MILLION MILES OF DAMAGE TO MOTORCYCLES IN ACCIDENTS FOR MRC AND CONTROL GROUPS

TOtal Wuberof Accidents

cost

209 92

MRC Control

lMRC

significantly

lower

Mean cost Per Accident

($1

Total cost Per Million Miles

0)

w

48,485

231.P

73,365

31,465

342.0

66,239

(e < .05).

drivers used boots. This suggests that the course should put more emphasis on this aspect of personal protection, because boots protect the rider’s ankles and lower legs. This study also corroborated the earlier evaluation’s findings that loss of control, including sliding on wet, icy, and gravel pavements, accounted for more than half of the accidents. About 16% of the accidents overall involved another vehicle. The MRC group tended to have more accidents due to sliding on gravel and low-friction pavements than the control group had. On the other hand, the control group was involved in almost twice as many collisions with other vehicles. Perhaps the MRC drivers adopted a more defensive posture with respect to other vehicles, but lacked the skills necessary to identify low-friction surfaces and to control the motorcycle on them. The latter may be partly due to the lack of exposure to such surfaces during the course, which is usually given on dry asphalt or concrete areas.

The study found that both groups had about the same number and rate of moving violations. A regression analysis suggested that persons who had been cited for moving violations were less likely to wear helmets, were young, and had had more accidents. This suggests that attitudes about safety gear, inexperience, and other aspects of youth and inadequate skill and judgment are related to motorcyclists’ violations. There was no difference between the two groups in the number of accidents, with 19% of the MRC drivers and 15% of the control group drivers reporting at least one “accident” as defined inhis study. These percentages are quite similar to those of the previous study (22 % and 16 % , respectively). Moreover, the MRC group did not have a lower accident rate (86.7 per million miles) than the control group had (37.7 per million miles). The above findings contrast with those of Lakner (1984) who conducted a telephone

TABLE 9 PERCENTAGE DISTRIBUTION OF SEVERITY OF INJURIES ACCIDENTS FOR MRC AND CONTROL GROUPS

Accidents

MRC

Control

194

209

92

FROM

--W-W

Ho5pltalized

None

MillOt-

ROa

52.6

34.0

11.0

2.4

48.4

29.0

19.4

3.2

]ournal of Safety Research

TABLE 10 ESTIMATED MEDICAL COSTS OF INJURIES FOR MRC AND CONTROL GROUPS

Total cost Grocg

w

MRC

179.130

Contro1

123,810

cost

Mean Cost Per Accident

Per Million Miles

($1

($1

857a 1,331

271,050 259,550

aNot significantlylower.

survey of a sample of MRC graduates and a sample of other motorcycle drivers and reported a lower accident rate for those who had taken the course. This is the only such finding in the literature, although an evaluation of the U.S. Air Force’s motorcycle rider program suggested that the program achieved a reduction in accidents (Shepard, 1986). However, no mileage exposure data were used in that evaluation which reported that, although registrations increased, “mishaps” and fatalities decreased in 1984 and 1985. In order to control for some of the factors that differentiated the MRC and control groups, such as age and years licensed, these factors were taken into account in calculating the accident rates. When this was done, there was no evidence that the MRC group had a lower accident rate. However, it was clear that, in both groups, older drivers and those who had been licensed longer had lower accident rates. In addition, those who drove more miles had a lower accident rate. This suggests that immediate exposure (i.e., mileage), in addition to the long-term quasiexposure factors described by age and years licensed, helps to maintain a safer level of performance. Perhaps, like piloting an aircraft, proficiency needs to be maintained by regular exposure. A training and education program, such as the MRC, may have its greatest effect in the early exposure of its graduates. Therefore, the accident rates of MRC and control drivers were evaluated during their first and second years after licensing. These compariWinter 1988Nolume 19/hkmber 4

sons yielded no evidence that the MRC group had lower accident rates than the control group. In order to evaluate the severity of the accidents of drivers in the MRC and control groups, the damage to the motorcycles and the severity of injuries were measured. The mean cost of damage to motorcycles in accidents was significantly less for the MRC group than for the control group, indicating that the MRC drivers’ accidents were less severe. The damage cost rate per million miles was not much different, however. This indicates that, when exposure is considered, there was no difference between the two groups in the cost of damage to the motorcycles. Although the mean cost of medical treatment per accident was lower for the MRC group than for the control group, the difference was short of significance at the .05 level. Moreover, the treatment cost per million miles was not lower for the MRC group. In the earlier study, the MRC group’s mean treatment costs per accident were found to be significantly less than those of the control group. Overall, the results of this larger evaluation of the MRC were similar, although slightly less positive, than those of the earlier study. The greater use of safety clothing by the MRC graduates probably was a factor in their lower (but not quite significantly different) injury severity. Likewise, their accidents were probably less severe as indicated by the lower costs of damage to their motorcycles. This lower severity may also have been due to the MRC drivers’ somewhat lower exposure on high-speed roads and at night and to their riding motorcycles with smaller engines than those of the control group. It may also have been due to the fact that smaller motorcycles are less costly to repair, In addition, MRC graduates were more conscious of safety to start with as shown by the fact that they used safety belts in automobiles more often than did the control subjects. About 79% of the accidents of the MRC group involved only a loss of control of the motorcycle, suggesting that the course should put more emphasis on vehicle handling skills, especially on gravel and wet pavement. Perhaps, riding at low speeds on grass could be used as a relatively safe tech195

nique for learning vehicle control skills on slippery surfaces. To some extent, the MRC:RSS (Motorcycle Rider Course: Riding and Street Skills), which was implemented in our program in Illinois in 1986 and which puts more emphasis on turning and braking than the MRC, is a step in the right direction. However, it still fails to provide any experience on wet or gravel surfaces. Finally, as mentioned earlier, this study found that about 30 % of those who had taken the MRC reported that they did not drive motorcycles. Although this might be thought to be a negative finding, it can also be considered a very positive one. For those persons who elected not to continue driving a motorcycle, the MRC program provided an opportunity to learn to ride a motorcycle in a safe environment. If these individuals had decided to learn to ride on streets and highways, they may have had an accident. It may be that the greatest benefit of the course is that it allows people to learn to ride in a safe environment and then decide if they want to ride in traffic. The number of accidents that may have been prevented is difficult to estimate, but it is well knownindeed has been shown by this study-that those with little exposure are at greatest risk.

196

REFERENCES Buchanan, L. S. (1987, January). Results of the motorcycle rider education evaluation project. Motorcycle and Moped Committee, Transportation Research Board. Jonah, B. A., Dawson, N. E., & Bragg, W. E. (1982). Are formally trained motorcyclists safer? Accident Analysis and Prevention, 14, 247-255. Laknery E. (1984). A survey of motorcycle riders in Illinois. Chamnairm-Urbana: Universitv of Illinois Survey Resear& Liboratory. McSwain, N. E., Willey, A., & Janke, T. H. (1985). The impact of reenactment of the motorcycle helmet law in Louisiana. Proceedings of the 29th Annual Conference of the American Association for Automotive Medicine, 425-446. Mortimer, R. G. (1984). Evaluation of the motorcycle rider course. Accident Analysis and Prevention, 16, 63-71. Mortimer, R. G., & Petrucelli, E. (1984). Cost of hospitalization of injured motorcyclists. Proceedings of the 28th Annual Conference of the American Association foT Automotive Medicine, 225-236. Osga, G. A. (1980). An investigation of the riding experience of MSF course participants in South Dakota (Report HFL-80-2). Vermillion: University of South Dakota. Raymond, S., & Tatum, S. (1977). An evaluation of the effectiveness of the RAC/ACU motorcycle training scheme. Road Safety Research Unit, Department of Civil Engineering, cniversity of Salford.Satten, R. (1980). Analysis and evaluation of the motorcycle rider course in thirteen northern Illinois counties. Proceedings of the International Motorcycle Safety Conference, 145-193. Shepard, R. (1986, February). From five sides. Safe Cycling, pp. 10-11.

Journal of Safety Research