Abstract
Abstract: :
Purpose: To compare three visual acuity chart tests as a function of age in pre-school children. Methods: Vision screening was performed on 253 pre-school children (81 three-year-olds; 108 four-year-olds; and 64 five-year-olds) from the same socio-economic background. Using a multi-station format, two out of the three visual acuity chart tests (Tumbling E, Lea Symbol, and HOTV) were used during a single screening session. Guidelines for the protocol were based on the American Academy of Pediatrics recommendations for screening. To pass the visual acuity screening, the child was required to pass one visual acuity test. Children who could not complete the protocol were re-tested at a later date. Children who failed the screening were referred for a full eye examination. Results: The Tumbling E, Lea Symbol and HOTV charts were completed more often by older children than the 3 year-old group (Pearson Chi-square: df- 4, p=0.052; p=0.012; p=0.0001). Within each age group, more 3 year-olds were re-tested on the Tumbling E and HOTV than the Lea Symbol Chart, (Chi Square: 28.4, df=2, p<0.05) and more 4 year-olds were re-tested on the Tumbling E than the other two tests (Chi Square: 17.97, df=2, p<0.05). Conclusion: Testability changes significantly with age. The Lea Symbol Chart is more likely to be completed by young children. The HOTV chart is as effective as the Lea Symbol Chart for the older children when socio-economic factors are held constant.
Keywords: 620 visual acuity • 310 aging: visual performance • 589 strabismus: diagnosis and detection