Assisting the older driver - SWOV

Assisting the older driver
the indexed lethality (that of the 30‐39 year olds is set at 1) begins to increase
at 55 years old and, at 85, reaches a level that is four times higher than that
for the 30‐39 year olds. With an equal fatality rate for all age groups, this
would mean that the older one gets, the more the fatality rate of a driver is
dominated by the vulnerability factor, and the less it is influenced by crash
involvement. Therefore, it is expected that the high fatality rate of older
drivers is the result of a slightly larger involvement in fatal crashes and a
much greater vulnerability, whereas the high fatality rate of young drivers is
the result of a considerably larger involvement in fatal crashes and a slightly
greater vulnerability. For this last conclusion, a reference should be made to
the disrupting influence of crash type on lethality. The generally greater
severity of crashes of young drivers may be completely responsible for their
higher lethality. This means that the greater vulnerability of young drivers as
shown in Figure 1.5 may be the mere result of using lethality to measure
vulnerability.
Vulnerability index (30‐39 year olds =1)
5
4
3
2
1
0
18‐19
20‐24
25‐29
30‐34
35‐39
40‐44
45‐49
50‐54
55‐59
60‐64
65‐69
70‐74
75‐79
80‐84
85‐89
90+
Figure 1.5. Vulnerability index: number of fatalities per 100 injured in the
age group concerned (1996‐1998). Source: Ministry of Transport, Public
Works and Water Management.
The large share that the vulnerability factor has in the involvement of older
drivers in fatal crashes was for Koornstra (1998) reason to believe that the
road safety measures taken within the framework of sustainable safety can
indeed lower the general crash rate, but that the fatality rate of older road
users will always remain higher than average. Some comments can be given
on this. First of all, it may be expected that certain vehicle measures will have
a greater effect on the fatality rate of older drivers than on the average
20