title: A population-based examination of the visual and ophthalmological characteristics of licensed drivers aged 70 and older.
abstract: BACKGROUND
  Safe driving performance depends on visual skills yet little is known about the prevalence of vision impairments in older drivers and the eye conditions that cause them. This study is a population-based examination of the prevalence of vision impairment and major ophthalmological conditions among drivers aged 70 and older.
  
  
  METHODS
  The source population was a random sample of 2,000 licensed drivers aged 70 and older residing in north central Alabama. All had driven within the past 3 months. Binocular visual acuity and contrast sensitivity were assessed. The Useful Field of View subtest 2 and Trails B assessed visual processing speed. Ophthalmological diagnoses for cataract, intraocular lens placement, glaucoma, diabetic retinopathy, age-related macular degeneration, and diabetic retinopathy were obtained through medical records from the most recent eye examination.
  
  
  RESULTS
  Ninety-two percent of drivers had visual acuity of 20/40 or better; only two drivers (0.1%) had acuity worse than 20/100. Ninety-three percent had normal contrast sensitivity (≥1.5). About 40% had slowed visual processing speed (44%, Useful Field of View; 38%, Trails B). The most common eye condition was cataract, with more than half having cataract in one or both eyes (56%); yet by the 80s and 90s, the prevalence was low, with most drivers having undergone cataract surgery and intraocular lens placement.
  
  
  CONCLUSIONS
  This population-based study suggests that serious impairment in central vision-visual acuity or contrast sensitivity-is rather uncommon in older drivers; however, slowed visual processing speed is common.
authors.affiliation: Department of Ophthalmology, School of Medicine, University of Alabama at Birmingham, Birmingham, AL 35294-0009, USA. owsley@uab.edu
authors.forename: Cynthia
authors.initials: C
authors.lastname: Owsley
authors.forename: Gerald
authors.initials: G
authors.lastname: McGwin
authors.forename: Karen
authors.initials: K
authors.lastname: Searcey
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001334:Automobile Driving; D005128:Eye Diseases / Q000175:diagnosis / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008297:Male; D015995:Prevalence; D014786:Vision Disorders / Q000175:diagnosis / Q000453:epidemiology*