ReviewPrevalence of Myopia and Refractive Changes in Students From 3 to 17 Years of Age
Section snippets
Subjects and Methods
The subjects of our present study were all students in the same kindergarten, primary school, junior high school, and senior high school affiliated with the national universities in Nara, Japan. The school children were selected from a pool of applicants. Annual mass ophthalmologic examinations were conducted at the schools from 1984 to 1996 by the same examiners throughout the entire period, with the same methodology and criteria. The total numbers of examinees were as follows: 1,940
Results
The age-specific frequency distribution of refractive errors for 6-year-old students (defined in this study as students in the first grade of primary school) and for 12-year-old students (defined in this study as students in the first grade of junior high school) during the 13-year period is shown in Fig. 1A-M. For 6-year-old students, the +1 D group has a sharp curve with a peak, and no changes were observed in this distribution throughout our study. Conversely, for the 12-year-old students,
Discussion
The age-specific frequency distribution of refractive errors remained similar for 6-year-olds during the 13 years studied, but myopia gradually increased in the 12-year-olds. The incidence of myopia among students older than 7 years was greater in 1996 than in 1984. In this 13-year period, the prevalence of myopia increased from 49.3% to 65.6% in 17-year-olds. This dramatic increase in the prevalence of myopia may be related to changes in physique (i.e., the reported differences in the results
Acknowledgements
The authors have no proprietary interest in products or techniques described in this article.
References (14)
Changes in refraction during life
Br J Ophthalmol
(1953)- et al.
Ophthalmic optics and refraction
The importance of heredity and environment in the etiology of low myopia
Acta Ophthalmol (Copenh)
(1981)- et al.
Progression of myopia in youthage of cessation
Am J Optom Physiol Opt
(1983) - Japanese Ministry of Education, Science and Culture: Growth condition. Report on School Health Survey, 1994, pp...
- Japanese Ministry of Education, Science and Culture: The morbidity rate of refractive errors (visual acuity less than...
Analysis of school myopia using the Nidek auto-refractometer AR-3000, IIobservation of frequency distribution of pupil refraction
Folia Ophthalmol Jpn
(1984)