A visual survey of school children in Hong Kong

Abstract

Myopia is the major refractive anomaly among Hong Kong Chinese school children. The aims of this survey were to establish guidelines for the vision health care system and to study some possible influences on the aetiology of myopia. A total of 1247 school children aged from 6–17 years were surveyed and screened. The prevalence of myopia increased with age from 20 per cent at die age of six years to about 74 per cent at the age of 16–17 years. Major findings of this study were diat 58 per cent of the school children failed the screening according to the criteria. Refractive errors in die range from -0.75 to +1.25 dioptre spherical equivalent were considered a ‘PASS’. Any refractive error beyond diis range was considered ‘FAIL’. The failure rate was highest at age 10 to 12 years. Among die ‘FAIL’ group, 40 per cent of die subjects had never had vision examination before. The high failure rate from die screening definitely revealed die need to improve die present vision healdi care system. An improved screening program is suggested. No statistically significant association was found between refractive errors and die number of hours of close work, academic performance, or parents' refractive errors. Aldiough die present study has not given any specific clues to die development of myopia, it has indicated diat die aetiology of myopia might be multifactorial.