Test of divided visual attention predicts automobile crashes among older adults.

Abstract

JAMA Visual Processing Impairment and Crash Risk Among Older Adults Cynthia Owsley, PhD; Karlene Ball, PhD; Gerald McGwin Jr, MS; Michael E. Sloane, PhD; Daniel L. Roenker, PhD; Milton F. White, MD; E. Todd Overley, OD, MS Context Crash risk in older drivers has been associated with visual acuity loss, but only weakly so, suggesting other factors contribute. The useful field of view is a measure that reflects decline in visual sensory function, slowed visual processing speed, and impaired visual attention skills. Objective To identify whether measures of visual processing ability, including the useful field of view test, are associated with crash involvement by older drivers. Design Prospective cohort study with 3 years of follow-up, 1990-1993. Setting Ophthalmology clinic assessment of community-based sample. Patients A total of 294 drivers aged 56 to 87 years at enrollment. Main Outcome Measure Motor vehicle crash occurrence. Results Older drivers with 40% or greater impairment in the useful field of view were 2.2 times (95% confidence interval, 1.2-4.1) more likely to incur a crash during 3 years of follow-up, after adjusting for age, sex, race, chronic medical conditions, mental status, and days driven per week. This association was primarily mediated by difficulty in dividing attention under brief target durations. Conclusion Reduction in the useful field of view increases crash risk in older drivers. Given the relatively high prevalence of visual processing impairment among the elderly, visual dysfunction and eye disease deserve further examination as causes of motor vehicle crashes and injury. 1998;279:1083-1088.