To investigate the prevalence of myopia and its influencing factors in an epidemiologic study of conscripts living in Gyeongsangnam-do, Ulsan and Busan.

A cross-sectional study was conducted in 19-year-old conscripts in Gyeongsangnam-do, Ulsan and Busan. Health checkup data of the conscripts were collected and analyzed along with subjective visual acuity, noncycloplegic autorefraction test, biometric data, and social factors such as education level and residence area. Myopia and high myopia were defined as having a refractive error of more than -0.5D, -6.0D, respectively. To analyze the social and biometric effects, we classified social factors into three groups and biometric factors into five groups. The estimated myopic prevalence was calculated adding excluded conscripts who scored under 0.5 on the subjective visual acuity test and missed autorefraction data. Data analysis was performed with descriptive analysis and the chi square test for trends using the Statistical Package for the Social Sciences (SPSS) version 14.0K.

From 66,917 eligible conscripts, 50,243 were analyzed. The prevalence of myopia and high myopia in 19-year-old men in Gyeongsangnam-do, Ulsan and Busan were 45.60% (95% CI: 45.17~46.03) and 11.50% (95% CI: 11.23~11.77). The estimated myopic prevalence using 66,917 eligible conscripts was 54.31% (95% CI: 53.88~54.74).

The prevalence of myopia and high myopia and the estimated prevalence of myopia in 19-year-old men in Gyeongsangnam-do, Ulsan and Busan were 45.60%, 11.50% and 54.31%, respectively.