Some states also have a visual field requirement.
As people grow older, age-related vision change is inevitable, and many older Americans may be at risk perhaps unnecessarily of losing their driving licenses and their independence. Recognizing that there was little correlation between traffic accident statistics and visual acuity, Dr. Higgins traveled on a research fellowship to the Queensland University of Technology in Brisbane, Australia. There, on a closed driving track, he studied how varying levels of vision affect driving performance, by how much and which types of vision tests were most predictive of changes in driving. Overall, the results showed that diminished vision caused selective loss in some aspects of driving performance, but others were unaffected. The next steps for Dr. Higgins will be to conduct tests with the aid of a driving simulator to evaluate scenarios that might prove particularly challenging for individuals with vision loss.