OBJECTIVES: There is no consensus yet on how to determine which patients with cognitive impairment are able to drive a car safely and which are not. Recently, a strategy was composed for the assessment of fitness to drive, consisting of clinical interviews, a neuropsychological assessment, and driving simulator rides, which was compared with the outcome of an expert evaluation of an on-road driving assessment. A selection of tests and parameters of the new approach revealed a predictive accuracy of 97.4% for the prediction of practical fitness to drive on an initial sample of patients with Alzheimer's dementia. The aim of the present study was to explore whether the selected variables would be equally predictive (i.e. valid) for a closely related group of patients, i.e. patients with Mild Cognitive Impairment (MCI).
METHODS: Eighteen patients with mild cognitive impairment completed the proposed approach to the measurement of fitness to drive, including clinical interviews, a neuropsychological assessment and driving simulator rides. The criterion fitness to drive was again assessed by means of an on-road driving evaluation. The predictive validity of the fitness to drive assessment strategy was evaluated by Receiver Operating Characteristic (ROC) analyses.
RESULTS: Twelve patients with mild cognitive impairment (66.7%) passed and 6 patients (33.3%) failed the on-road driving assessment. The previously proposed approach to the measurement of fitness to drive achieved an overall predictive accuracy of 94.4% in these patients. The application of an optimal cut-off resulted in a diagnostic accuracy of 100% sensitivity towards unfit to drive, and 83.3% specificity towards fit to drive. Further analyses revealed that the neuropsychological assessment and the driving simulator rides produced rather stable prediction rates, whereas clinical interviews were not significantly predictive for practical fitness to drive in the MCI patient sample.
CONCLUSIONS: The selected measures of the previously proposed approach revealed adequate accuracy in identifying fitness to drive in patients with Mild Cognitive Impairment. Furthermore, a combination of neuropsychological test performance and simulated driving behaviour proved to be the most valid predictors of practical fitness to drive.
- Fitness to drive
- mild cognitive impairment
- neuropsychological assessment
- driving simulator
- on-road test
- OLDER DRIVERS
- AMERICAN ACADEMY
- DRIVING ABILITY