Assisting the older driver - SWOV

Assisting the older driver
In the present study, the functions of the driver information system of
Entenmann and Küting (2001) were combined with the ‘gap selecting’‐
function tested in the EDDIT‐project. A driver assistance system was tested
which not only provided the driver with information on speed limits, oneway
streets, and priority regulations, but also actively warned the driver to
reduce speed when approaching an intersection at which the sight on the
crossing street was obstructed by buildings, and which indicated when it
was safe to join or cross traffic streams at busy intersections. Analogous to
the idea of Entenmann and Küting, this assistance system was intended to
reduce workload at the intersection by timely informing the driver about
what to expect. If the driver either consciously or subconsciously knows
what to expect, it is more likely that he will select the correct mental schema
for safely passing the intersection. This mental schema will simplify the
driving task and will prevent errors. The present study was designed to
evaluate the driver assistance system in this respect. The system was
evaluated in terms of effects on workload, driving performance, and user
acceptance.
While evaluating the system, the effects on driving behaviour were
compared between older (70 years and older) and younger persons (30‐50
years old). The age boundaries of the first group were chosen as a
compromise between the preferred group of people aged 75 and above – the
group of older adults that has a fatality rate which is higher than average
(OECD, 2001; SWOV, 2005) – and the availability of participants of a certain
age. The group of people aged 30‐50 was chosen as the comparison group.
People of this age group were expected to have considerable driving
experience and not yet to be confronted with functional limitations. As the
information provided by our information system was selected based on the
functional limitations of older drivers, it was expected that older drivers
would benefit more from the information given in terms of reduced
workload and, as a result, would also be more willing to accept the system.
Realizing that ageing is a process that does not start at the same age for every
person nor continues at the same rate, with the result that drivers having the
same age (as in years since birth) can differ in the number and severity of
their functional limitations, age was both considered chronologically and
functionally (for a discussion on the prediction of functional age see Birren &
Renner, 1977, p. 15‐17). Functional age was based on scores on three tests of
cognitive functioning, relating to reaction time, selective attention, and
visual‐motor coordination. Persons scoring well on the average of these three
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