Prevalence of color vision deficiency and its correlation with amblyopia and refractive errors among primary school children

Purpose: to determine the prevalence of color vision deficiency (cvd) and its correlation with amblyopia and refractive errors among primary school children. methods: in this population-based cross-sectional study,2160 children were selected from 36 primary schools; 60 students were from each school (10 students in each grade),with equal sex distribution. a complete eye examination including refraction using a photorefractometer,determination of visual acuity (va) and color vision using a yang vision tester,and evaluation of ocular media opacity using a direct ophthalmoscope was performed. children who could not answer at least 4 plates of the ishihara color test were considered as color vision deficient subjects. amblyopia was determined if pinhole va was worse than 0.3 logmar (equal to 20/40). results: the prevalence of cvd was 2.2% (95% ci: 1.5% to 3%) which was higher in male subjects (37 [3.5%] boys vs. 11 [1.0%] girls,p < 0.001). mean va was lower among students with cvd as compared to normal color vision children (p = 0.035) and amblyopia was observed in 8.3% (95% ci: 0.2% to 16.4%) of patients with cvd versus 2.1% (95% ci: 1.5% to 2.08%) of children with normal color vision perception (p = 0.005). a statistically significant correlation between lower va and cvd was observed (p = 0.023). conclusion: although cvd was correlated with lower va and amblyopia,there was no relationship between cvd and the type of amblyopia,refractive error,anisometropia or strabismus. © 2015 journal of ophthalmic and vision research.