This pilot study was carried out to investigate the association with age and crash involvement of: (1) the British number plate test; (2) some alternative tests of basic visual function (Ergovision screener: photopic visual acuity, mesopic visual acuity, dynamic visual acuity, low contrast visual acuity, visual fields, dazzle recovery, stereopsis, heterophoria and colour vision); and (3) a test of higher order perceptual function (Useful Field of View Visual Attention Analyser). Drivers (67 with crashes, 217 without) were screened at 29 venues in England and North Wales. Age, gender, annual mileage and self reported "at fault" crash involvement (over the last 5 years) were recorded. Associations between vision screening scores versus age and crash involvement were tested for statistical significance using Chi-square with Yates' correction. The main conclusions arising from this study were that: (1) The British number plate test showed no significant association with age or crash involvement; (2) Many of the basic visual functions deteriorated significantly with advancing age. However, only a derivative of the test for low contrast visual acuity (referred to as contrast susceptibility) exhibited significant associations with crash involvement in younger and older drivers; and (3) Visual attention also significantly reduced with advancing age but no significant association with crash involvement was demonstrated - although the association recorded for older drivers exceeded that found for younger drivers.
Abstract