Drivers with dementia may have a higher accident risk than comparable drivers without dementia, but the results of studies are ambiguous, as are those linking neuropsychological impairments to driving safety. This study sought to identify neuropsychological tests that could identify dementia patients who are not safe to drive, and to develop a brief test procedure for screening their driving safety. Participants were recruited from the Memory Disorders Study Unit at Repatriation General Hospital, Daw Park. Standardised on-road driving assessments were conducted by the Driver Assessment Rehabilitation Service of the University of SA, and awarded a pass or fail grade. Neuropsychological tests were chosen in six areas of functioning. A total of 55 dementia patients participated, of whom 32 passed the driving test, while 23 failed. Drivers who failed performed more poorly than those who passed, in all neuropsychological test domains, but much of this difference was due to greater cognitive decline. After adjustment for cognitive decline (the Mini Mental State Examination), only the Trail Making Test Part A and the Block Design test successfully identified drivers who failed the driving test. Combining these three tests comprises a potential screening procedure for identifying dementia drivers at risk. This procedure identified 83% of fails and 91% of passes, and should be validated in a new sample. (Author/publisher)
Abstract