Chronological age and age-related cognitive deficits are associated with an increase in multiple types of driving errors in late life

Objective: Older driver research has mostly focused on identifying that small proportion of older drivers who are unsafe. Little is known about how normal cognitive changes in aging affect driving in the wider population of adults who drive regularly. We evaluated the association of cognitive function and age with driving errors.

Method: A sample of 266 drivers aged 70 to 88 years were assessed on abilities that decline in normal aging (visual attention, processing speed, inhibition, reaction time, task switching) and the UFOV®, which is a validated screening instrument for older drivers. Participants completed an on-road driving test. Generalized linear models were used to estimate the associations of cognitive factors with specific driving errors and number of errors in self-directed and instructor navigated conditions.

Results: All error types increased with chronological age. Reaction time was not associated with driving errors in multivariate analyses. A cognitive factor measuring speeded selective attention and switching was uniquely associated with the most errors types. The UFOV® predicted blind-spot errors and errors on dual carriageways. After adjusting for age, education, and gender, the cognitive factors explained 7% of variance in the total number of errors in the instructor-navigated condition and 4% of variance in the self-navigated condition.

Conclusion: We conclude that among older drivers, errors increase with age and are associated with speeded selective attention, particularly when that requires attending to the stimuli in the periphery of the visual field, task switching, errors inhibiting responses, and visual discrimination. These abilities should be the target of cognitive training.