ON-ROAD DRIVING ASSESSMENT AND ROUTE DESIGN FOR DRIVERS WITH DEMENTIA

Background: Dementia causes progressive loss of cognitive capacities, impairs daily living skills and to varying degrees, influences driver performance and safety. Eventually drivers affected by dementia must stop driving so... [ view full abstract ]

Background:
Dementia causes progressive loss of cognitive capacities, impairs daily living skills and to varying degrees, influences driver performance and safety. Eventually drivers affected by dementia must stop driving so they do not harm themselves or others. Cessation of driving can result in loss of mobility and social connections. Therefore, assessing drivers with dementia is important but susceptible to possible biases, including unreliable driving performance measures or driving routes that are inconsistent in the levels of difficulty of the driving tasks.
Method:
Drivers with dementia (n 117; age 48 – 88; MMSE 10 - 30) underwent a 60 minute, set route on-road driving assessment in Adelaide South Australia consisting of 110 pre-programmed observation points. Drivers were assessed by an occupational therapist; outcome was determined by consensus with a professional driving instructor.
Results:
The study identified 80 sufficiently challenging driving tasks and described the relationship of driving error to that task, for example, critical errors at unguided intersections.
Conclusion:
Each on-road assessment task inclusion has the potential to elicit one or more error type and the discriminatory task items are congruent with previous research, suggesting high construct validity. The results of the task-demand by error type analysis identified a list of task items that can be applied to assessment route design.
Application to Practice:
This study describes a range of suitably challenging items and sequences of driving tasks that can be used to enhance the consistency of design inclusions in on-road assessment routes and thus improve assessment of drivers with dementia.