Evaluation of vision screening of 5-15-year-old children in three Tongan schools: comparison of The Auckland Optotypes and Lea symbols

• Published in: Clinical and experimental optometry 2020-05, Vol.103 (3), p.353-360
• Main Authors: Hamm, Lisa M, Langridge, Fiona, Black, Joanna M, Anstice, Nicola S, Vuki, Mele, Fakakovikaetau, Toakase, Grant, Cameron C, Dakin, Steven C
• Format: Article
• Language: English
• Subjects: Acuity; Children; electronic visual acuity; Elementary schools; Medical screening; Myopia; optotypes; Pacific; Public health; screening; Tonga; Vision
• ISSN: 0816-4622; 1444-0938
• DOI: 10.1111/cxo.12958

Comprehensive vision screening programmes for children are an important part of public health strategy, but do not exist in many countries, including Tonga. This project set out to assess: (1) the functional vision of children attending primary schools in Tonga and (2) how a new recognition acuity test (The Auckland Optotypes displayed on a tablet computer) compares to use of a standardised eye chart in this setting. Children from three Tongan primary schools were invited to participate. Acuity testing was conducted using a standardised recognition acuity chart (Lea symbols) and the tablet test displaying two formats of The Auckland Optotypes. Measures of ocular alignment, stereo acuity and non-cycloplegic photorefraction were also taken. Parents of 249 children consented to participate. One child was untestable. Only 2.8 per cent of testable children achieved visual acuity worse than 0.3-logMAR in the weaker eye. Results from the Spot Photoscreener suggested that no children had myopia or hyperopia, but that some children had astigmatism. The tablet test was practical in a community setting, and showed ±0.2 logMAR limits of agreement with the Lea symbols chart. The sample of children in Tongan primary schools had good functional vision. A modified version of the tablet acuity test is a promising option for vision screening in this context.