Abstract: Objective To explore the applicability of Titmus and Yan's third-generation stereoscopic test charts in preschool children. Design Cross-sectional survey. Participants Stratified and clustered 1021 children aged 3-6 years from 5 kindergartens in Haidian District, Beijing. Methods All children were examined for visual acuity, ocular deviation, Titmus stereo vision and Yan's third-generation stereo vision. Successful inspection was defined as being able to recognize the qualitative plates pattern or clearly stating that there was no hidden pattern in the qualitative plates. Successful inspection rate of children of different ages was measured. The differences in the stereo acuities of children of different age groups and the differences in the results of two stereo vision examinations were compared. Main Outcome Measures Stereo acuity. Results Test ability of the Titmus stereo charts was 91.2% while the Yan's third-generation stereoscopic test charts was 86.0% for 3 years-old children. Successful inspection rate of two tests increased with age. Among children who can complete the test, Titmus stereo acuity charts that can be achieved by more than 90% of children were 100″ for 3 years-old children, 80″ for 4 years-old children and 60″ for 5-6 years-old children, while Yan's third-generation stereo acuity charts was 60″ in all age groups. The percentage of 60″ by Titmus test was gradually increased with ages and statistically different between the 3-4 years-old children (χ2=55.578, P=0.000), 4-5 years-old children (χ2=7.989, P=0.005). The percentage of 60″ by the Yan's third-generation stereopsis charts was over 90% in 3 years-old children and was not statistically different between any two adjacent age groups. There were statistically significant differences between the two stereoscopic tests (χ2=68.284, P=0.000). With the increase of age, the difference between the two tests decreased and there was no statistical difference in 5 years-old (P=0.070) and 6 years-old group (P=0.146). Conclusion Titmus charts has high test ability for under-age children. The normal reference values of the two tests for preschool children were different. The normal reference value of the two tests in 5 years-old or more children tends to be unified. (Ophthalmol CHN, 2020, 29: 339-343)

Key words: stereopsis, child, preschool