Epidemiological Study of the Development of Visual Acuity in Preschoolers Aged 3 to 6 in the Shenzhen Area

Purpose： To investigate the visual acuity of preschoolers aged 3 to 6 years in Shenzhen of China. Methods： Visual acuity was measured in preschoolers from eight kindergartens in Shenzhen. Results： A total of 1147 children completed the visual acuity test.There were 77 boys and 62 girls aged 3 years, 259 and 216 aged 4, 193 and 160 aged 5 and 94 and 86 aged 6. The mean visual acuities of children aged 3, 4, 5, and 6 years were 0.51±0.10, 0.54±0.13, 0.65±0.14, and 0.71±0.17, respectively. The visual acuity was significantly improved with increasing age （P=0.000）. Conclusion： For preschoolers aged 3 to 6, the visual acuity continuously develops and improves. Therefore, age should be considered when diagnosing amblyopia in children.