A community based survey of cognitive functioning, highway-code performance and traffic accidents in a cohort of older drivers

Abstract

Background: The DVLA allows driving in early dementia contingent on regular medical assessment. GPs and psychiatrists require validated and accessible assessments. Some studies have suggested that cognitive testing has utility in the assessment of driving capacity in elderly drivers. One study raises the possibility of using a highway-code questionnaire as an adjunct to these tests.

Method: Two hundred drivers over the age of 65 were randomly selected from two GP surgeries. Baseline assessment comprised completion of a Highway Code questionnaire (DPHC-98), the Mini Mental State Examination (MMSE) and an abbreviated version of the Alzheimer's Disease Assessment Scale Cognitive Subsection (EURO-ADAS). A history of road traffic accidents (RTAs) over the preceding 5 years was obtained. At 12-month follow-up interview driving status of the subject and occurrence of RTAs were recorded. Predictive power of DPHC-98 and cognitive testing with regards RTAs were examined through logistic regression analysis.

Results: Performance on the Highway Code questionnaire was identified as the only significant regression factor in the prediction of prospective RTAs. However, none of the logistic regression models were able to identify any drivers involved in RTAs either retrospectively or prospectively.

Conclusion: Cognitive tests are not linked with risk of driving accidents in older adults in any useful way.