to assess the prevalence of refractive errors and Red-Green color vision deficiency among preschool students in Asadabad, Iran.

In a cross-sectional study 441 students selected through a multi staged sampling method. The examinations included cycloplegic refraction, UCVA, BCVA and Cover test. Based on cycloplegic spherical equivalent refractive error hyperopia defined as +2.00 diopter or more, myopia as -0.50 D or worse and Astigmatism as cylinder equal to or worse than -0.50 D. Color vision testing was performed with Ishihara plates (38-plate edition). More than two misreading on the test was considered a failing criterion. Data were analyzed by SPSS-18 using Chi-square test.

of the 441 participants, information was gathered of 428 students. The mean age of participants was 6.1±0.30 years old. The prevalence of uncorrected and optimal visual acuity of 20/40 or worse were 3.3% and 0.4% respectively. The spherical equivalent cycloplegic refractions mean was 0.83±0.52 diopters. 2.7% of the students had color vision deficiency that 53.3% and 46.7% of them were deutan and protan respectively.

the prevalence of refractive error was considerably high in this area. The prevalence of congenital red-green color vision deficiency among this age group is mid-range in comparison with other studies. It is needed to attention paid to preschool students’ examination by health system.