All kinds of age-related vision issues can cause consternation on the roads, and the first sign of a problem is often difficulty with nighttime driving. However, obtaining a measurement for night-driving abilities is elusive due to its subjective nature. That’s why researchers in Australia are looking for ways to universally quantify nighttime driving experiences.

The investigators are focusing on associations between drivers’ perceived vision‐related night‐driving difficulties and night‐time driving performance as measured on a closed‐road circuit that involved recognition, hazard avoidance and lane-keeping tasks. Subjects were tested both with and without intermittent glare. The participants were also asked to complete a vision and night-driving questionnaire (VND‐Q). Their vision was assessed using high‐contrast, photopic visual acuity (VA) and ratings of discomfort glare.

The team looked at these measures for 26 patients with a mean age of 71. They found that greater VND‐Q scores were significantly associated with poorer performance and that association was even stronger for performance with intermittent glare. Reduced VA was also associated with poorer night‐driving performance, but that association was weaker than for the VND‐Q scores. In contrast, ratings of discomfort glare were not significantly associated with driving performance.

Hopefully, this means that simply having patients complete the VND‐Q can foretell performance and provide doctors a useful instrument for assessing vision‐related night-driving difficulties, without anyone having to hit the road. 

Kimlin J, Black A, Wood J. Older drivers' self-reported vision-related night-driving difficulties and night-driving performance. Acta Ophthalmol. November 26, 2019. [Epub ahead of print].