Prevalence of color vision deficiencies and refractive errors among vocational road drivers enrolling for health Card, Shahrood- Semnan province

Background and aims: Considering the few published population-based studies about vocational driver vision, this study was conducted to determine the prevalence of color vision deficiencies and refractive errors in vocational drivers applying for a health card in Shahrood. Methods: In this cross-sectional study, among the vocational drivers of Semnan province who were registered to obtain/renew a health card at the occupational health center, 2856 eligible persons were included in the study. In all candidates, refractive errors and visual acuity (with and without correction) were measured, and color vision was tested using Ishihara pseudo-isochromatic plates. Results: Among 2856 participants with an average age of 38.09 ± 7.2 years (range of 23 to 61 years), 197 participants (6.89% of the population) had color vision disorders. 108 participants (3.78%) had deuteranomaly, 33 persons (1.15%) had protanomaly, 31 persons (1.1%) had deuteranopia, 23 persons (0.8%) had protanopia, and 2 persons (0.07%) were totally color blind. The average visual acuity of the right eye without correction was 0.81 ± 0.18 decimal and the left eye was 0.78 ± 0.17 decimal. These values were reported as 0.99 ± 0.01 and 0.99 ± 0.02 for the right and left eyes (respectively) with correction. The prevalence of myopia and hyperopia among color blinds was 18% and 9.7%, respectively, and in the entire studied population, it was 21.7% and 10.8%, respectively. Conclusion: Considering the importance of vision health in the study group and the fact that vocational drivers have reached these stages after obtaining all related driving licenses, their prevalence of CVD and refractive errors is considerable.