THE CONTRIBUTION OF COGNITIVE AND VISUAL ASSESSMENT TO THE PREDICTION OF DRIVING PERFORMANCE

As part of driving ability assessment procedures at Banstead Mobility Centre, clients with a disability associated with brain damage routinely complete medical, visual, cognitive, physical and in-car tests on the day of assessment and are contacted a year later for details of driving status (driver, learner driver, non-driver). This study investigates the contribution of the visual and cognitive aspects of this assessment procedure to the prediction of driving ability (defined by performance during the in-car test, driving status one year after assessment and accident involvement in the year following assessment) for 307 people who have had a stroke or head injury or who suffer from multiple sclerosis. Results indicate that some of the cognitive and visual tests used in the assessment process are more sensitive to the abilities of different groups than others. Cognitive test scores in particular highlight the specific difficulties of those with left sided brain dysfunction following a stroke, whereas visual assessment demonstrates the more widespread effects of trauma or the disease process, in the case of multiple sclerosis. As far as the predictive ability of the tests is concerned, it is clearly shown that although individual test scores cannot be significantly associated with quality of driving performance, groups of tests are more likely to be predictive. In this study, it was determined that a combination of cognitive test scores (primarily assessing higher-order processes associated with planning and organisation), a comprehensive visual assessment, past driving experience and age could accurately predict driving test performance during the in-car test for 80% of those assessed.