The effects of minimal field defects upon on-road driving performance

Abstract

The current Australian Medical Guidelines for holding a driver’s license provides a standard for peripheral visual field loss in which the remaining field should be no less than 120 degrees across the horizontal plane. Twentyfour patients fulfilling this requirement, were tested by the Sydney University Driving Rehabilitation team (comprising an Orthoptist, an Occupational Therapist and a Driving Instructor). These patients had conditions acquired following head injury, stroke or medical problems that often result in reduced peripheral vision. Both an off-road (clinical) assessment and an on-road (driving) assessment were undertaken. Reduced visual fields correlated significantly with reduced driving performance. It was concluded that clients with reduced peripheral fields require appropriate testing and rehabilitation to ensure safe driving performance.