title: Near-work activity and myopia in rural and urban schoolchildren in China.
abstract: OBJECTIVE
  To examine the prevalence of myopia in rural and urban schoolchildren in Xiamen, China, and to assess the impact of environmental factors on rates of myopia.
  
  
  METHODS
  Second-grade children attending either a city (n=119) or rural (n=91) school in Xiamen, China, were examined using cycloplegic autorefraction and biometry. Detailed questions on socioeconomic status, near-work activity, reading and writing habits, and family histories of myopia were asked in a face-to-face interview using a standard questionnaire.
  
  
  RESULTS
  The prevalence of myopia was 19.3% (95% confidence interval [CI], 12.3, 29) in the city and 6.6% (95% CI, 2.4, 14.3) in the countryside. The average hours per day children spent reading and writing outside of school was 2.2 hours in the city compared with 1.6 hours in the countryside (P<.0001). In both schools, the odds ratio for total reading and writing, adjusted for parental history of myopia, was 2.2 (95% CI, 1.1, 4).
  
  
  CONCLUSIONS
  These data suggest the prevalence of myopia is higher in the city than in the countryside. One possible explanation for these different rates could be that schoolchildren in the city spend more time reading and writing outside of school compared with children in the countryside. Myopic children in both the city and the countryside spent more time reading and writing compared with nonmyopic children. This increased near-work activity may contribute to the prevalence of myopia.
authors.affiliation: Department of Community, Occupational, and Family Medicine, National University of Singapore, Singapore.
authors.forename: S M
authors.initials: SM
authors.lastname: Saw
authors.forename: R Z
authors.initials: RZ
authors.lastname: Hong
authors.forename: M Z
authors.initials: MZ
authors.lastname: Zhang
authors.forename: Z F
authors.initials: ZF
authors.lastname: Fu
authors.forename: M
authors.initials: M
authors.lastname: Ye
authors.forename: D
authors.initials: D
authors.lastname: Tan
authors.forename: S J
authors.initials: SJ
authors.lastname: Chew
mesh_terms: D002648:Child; D002681:China / Q000453:epidemiology; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D009216:Myopia / Q000453:epidemiology*; D015995:Prevalence; D012029:Refraction, Ocular; D012424:Rural Population / Q000706:statistics & numerical data*; D012574:Schools; D012923:Social Class; D011795:Surveys and Questionnaires; D014505:Urban Population / Q000706:statistics & numerical data*; D014937:Work / Q000706:statistics & numerical data*