title: Visual function in professional truck drivers.
abstract: OBJECTIVE
  The purpose of this study was to examine the visual function of professional truck drivers at working age to find out whether older drivers had any defective function and should therefore be given less demanding duties at work.
  
  
  METHODS
  Of the 100 drivers invited to the study, 77 came to the examination, including 74 men and 3 women aged from 30 to 66 years (mean 50.3+/-10.3 years). In addition to the basic eye examination, visual fields, dark adaptation, contrast sensitivity, color vision, and glare sensitivity were studied.
  
  
  RESULTS
  Two drivers (2.6%) had an incipient cataract in one eye, four (5.2%) had slight fundus abnormalities, five (6.5%) had exo- or esotropia, and five (6.5%) had amblyopia. Visual acuity in the better eye varied from 0.4 to 1.2 (mean 1.06+/-0.17) and in the other eye from 0.1 to 1.2 (mean 0.96+/-0.23). Five drivers (6.5%) had inadequate visual acuity for a professional driver's license. Visual fields were interpreted as normal in all drivers. The results of the dark-adaptation, contrast-sensitivity, and glare testing showed values within normal ranges for all drivers. In the color-vision tests, five male drivers (6.8% of the men) had a slight congenital green defect, and two drivers had an acquired blue defect in one eye because of cataract and diabetes.
  
  
  CONCLUSIONS
  According to the present study, there is no need to give older drivers less demanding duties because of their eyes. However, one serious finding in the present study needs attention: the visual acuity was lower than that required for a professional driver's license in five drivers. Evidently, more regular checkups of visual acuity are needed for a professional driver's license.
authors.affiliation: Department of Ophthalmology, University of Kuopio, Finland.
authors.forename: M
authors.initials: M
authors.lastname: Mäntyjärvi
authors.forename: K
authors.initials: K
authors.lastname: Tuppurainen
authors.forename: H
authors.initials: H
authors.lastname: Rouhiainen
mesh_terms: D000221:Adaptation, Ocular / Q000502:physiology; D000328:Adult; D000368:Aged; D000375:Aging; D001334:Automobile Driving; D005260:Female; D006801:Humans; D008004:Licensure / Q000592:standards; D008297:Male; D008875:Middle Aged; D018986:Motor Vehicles; D016272:Occupational Health; D012016:Reference Values; D014786:Vision Disorders; D014792:Visual Acuity