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Driving Simulation in the Clinic: Testing Visual Exploratory Behavior in Daily Life Activities in Patients with Visual Field Defects
Published on: September 18, 2012
Visual function survey of commercial intercity vehicle drivers in Ilorin, Nigeria
B J Adekoya1, J F A Owoeye, F G Adepoju
1Department of Ophthalmology, Lagos State University Teaching Hospital, Ikeja, Nigeria. bjadekoya2007@yahoo.com
Objective:
To determine the prevalence of visual impairment among commercial intercity vehicle drivers (CIVDs) in Ilorin, Nigeria.
Design:
A cross-sectional descriptive study.
Participants:
Among the estimated 450 drivers operating in 5 motor parks for CIVDs in Ilorin, 399 drivers participated in the study.
Methods:
A structured questionnaire was administered at the motor parks to consecutive and consenting drivers, and basic ocular examinations were done.
Results:
Using the Federal Road Safety Commission's requirement for commercial drivers in Nigeria, the prevalence of drivers with inadequate visual acuity (VA) was determined to be 11.5%, and 3.3% had monocular blindness. The prevalence of abnormal colour vision and visual field loss was 4.3% and 5.5%, respectively. There was no statistically significant relationship between visual impairment (VA and visual fields) and involvement in road traffic accidents (p > 0.05). Uncorrected refractive error, cataract, and glaucoma were the commonest causes of visual defects. Three hundred thirty-seven drivers (84.5%) did not have their eyes tested at first licensing and 370 drivers (92.7%) did not have testing at least once during renewals.
Conclusions:
A significant number of CIVDs in Ilorin are operating with VA that is far below the expected for their class of licence, and another unacceptably high percentage did not undergo any form of ocular examination prior to obtaining their driving licence. There is a need for renewed efforts to enforce a compulsory basic ocular examination for all prospective commercial drivers, and to ensure that the visual requirement for driving is met.
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