Assisting the older driver - SWOV

Assisting the older driver
To identify characteristics of intersections that coincide with a higher
frequency of crashes involving older drivers, two types of intersections were
compared: (1) intersections at which relatively many crashes occurred
involving older drivers, and (2) intersections at which no crashes occurred
involving older drivers. The comparison of these intersections and their
characteristics was directed by expectations regarding the factors that
determine the difficulty of passing an intersection. Based on the literature on
task difficulty, information processing, and ageing and driving (e.g., Fuller,
2000, 2001; Hendy, East & Farrell, 2001; Brouwer, 2002b), it was expected that
for older drivers the difficulty of passing an intersection (i.e., crossing or
turning left or right at it), and hence the likelihood of a crash, is determined
by a combination of 1) the complexity of the traffic situation, 2) whether or not
the driver has to take a decision with regard to road users that are about to
cross his path (e.g., type of intersection, priority regulation or traffic lights
that guarantee a protected left‐turn), and 3) the availability of a proper mental
schema. Given the capabilities of the older driver, the task of passing an
intersection was only expected to be difficult if the traffic situation is
complex and the driver has to decide on how to deal with traffic that is about
to cross his path and the driver cannot bring his experience (and schemata) to
the job. The complexity of a traffic situation was expected to increase with 1)
the amount of information that has to be processed (e.g., number of lanes and
traffic signs, presence of pedestrian crossings), 2) a reduction of the quality of
the information (e.g., visibility of signs and pavement markings), and 3) the
presence of time pressure (e.g., presence of trees, houses or cars that block the
view of the intersection and reduce the time left to anticipate on what is
coming). The complexity of the traffic situation is the factor that was
expected to be the most sensitive to the age of the driver. Complex situations
put a severe strain on the sensory, perceptual and cognitive capacities of the
driver, and these capacities are often reduced in the older age group (see e.g.,
Brouwer & Ponds, 1994; Fisk & Rogers, 1997). For younger drivers, other
factors were expected to play a role in the likelihood of crashes, such as
whether or not the road layout offers drivers the opportunity to speed, and
the type of factors which Fuller classified under the heading of human
factors, such as emotions, alcohol and other drugs, stress, and distraction (see
Section 4.2.1).
Based on the abovementioned expectations, it was expected that a higher
crash involvement of older drivers would be connected with: a) a larger
amount and/or poorer quality of traffic‐related information (complexity), b) a
larger number of decisions to be made by the driver (decision), and c) larger
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