Abstract
Purpose: :
To determine the age and gender specific prevalence of myopia in Chinese school.
Methods: :
The Beijing Pediatric Eye Study is a population-based evaluation of the prevalence of myopia in school children in Greater Beijing. One school of each level (primary, junior high, senior high) was randomly selected from nine randomly selected districts out of 18 districts. In total, 15096 eligible children underwent refractometry and their parents underwent an interview. All students of the selected schools and their parents were asked to complete a detailed questionnaire, and the students underwent non-cycloplegic auto-refraction. Myopia was defined as spherical equivalent refractive error -1.0 diopters or less in the worse eye.
Results: :
Of the 16407 eligible students, 15,096 (92.01%) children (7769 (51.6%) girls) participated in the study, with a mean age of 13.2 ± 3.4 years (range: 7 to 18 years) and with 8860 (58.8%) participants were living in the rural region, and 6206 (41.2%) students living in the urban region. The mean refractive error was -1.67 ± 2.14 diopters for the right eyes and -1.50 ± 2.14 diopters for the left eyes. The mean cylindrical refractive error was 0.58 ± 0.57 diopters for the right eyes and 0.62 ± 0.63 diopters for the left eyes. Prevalence of myopia defined as refractive error ≤-1.00 diopters in the worse eye was overall 57.1 ± 0.4% (95%CI: 56.3, 57.8). Prevalence of myopia increased significantly (P<0.001) with age up to an age of 16 years from which onwards the prevalence of myopia was almost constant. Girls were significantly more myopic and more frequently myopic than boys (61.0% vs. 53.0%, P<0.001).
Conclusions: :
Compared with school children in other countries, school children in Greater Beijing are markedly more often myopic, with a prevalence of high myopia (<-8D) at 1.1%. Prevalence of myopia was associated with age (leveling off at 16 years), female gender and urban region of habitation.
Keywords: myopia • clinical (human) or epidemiologic studies: prevalence/incidence • refractive error development