title: Peripheral refraction in 7- and 14-year-old children in central China: the Anyang Childhood Eye Study.
abstract: OBJECTIVE
  To determine the distribution of peripheral refraction, including astigmatism, in 7- and 14-year-old Chinese children.
  
  
  METHODS
  2134 7-year-old and 1780 14-year-old children were measured with cycloplegic central and horizontal peripheral refraction (15° and 30° at temporal and nasal visual fields).
  
  
  RESULTS
  7- and 14-year-old children included 9 and 594, respectively, with moderate and high myopia (≤-3.0 D), 259 and 831 with low myopia (-2.99 to -0.5 D), 1207 and 305 with emmetropia (-0.49 to +1.0 D), and 659 and 50 with hyperopia (>1.0 D), respectively. Myopic children had relative peripheral hyperopia while hyperopic and emmetropic children had relative peripheral myopia, with greater changes in relative peripheral refraction occurring in the nasal than the temporal visual field. The older group had the greater relative peripheral hyperopia and higher peripheral J180. Both age groups showed positive slopes of J45 across the visual field, with greater slopes in the older group.
  
  
  CONCLUSIONS
  Myopic children in mainland China have relative peripheral hyperopia while hyperopic and emmetropic children have relative peripheral myopia. Significant differences exist between 7- and 14-year-old children, with the latter showing more relative peripheral hyperopia, greater rate of change in J45 across the visual field, and higher peripheral J180.
authors.affiliation: Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China.
authors.forename: Shi-Ming
authors.initials: SM
authors.lastname: Li
authors.affiliation: Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China.
authors.forename: Si-Yuan
authors.initials: SY
authors.lastname: Li
authors.affiliation: Anyang Eye Hospital, Henan Province, China.
authors.forename: Luo-Ru
authors.initials: LR
authors.lastname: Liu
authors.affiliation: Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China.
authors.forename: Yue-Hua
authors.initials: YH
authors.lastname: Zhou
authors.affiliation: Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China.
authors.forename: Zhou
authors.initials: Z
authors.lastname: Yang
authors.affiliation: Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China.
authors.forename: Meng-Tian
authors.initials: MT
authors.lastname: Kang
authors.affiliation: Anyang Eye Hospital, Henan Province, China.
authors.forename: He
authors.initials: H
authors.lastname: Li
authors.affiliation: Department of Ophthalmology, Zhengzhou Second Hospital, HenanProvince, China.
authors.forename: Xiao-Yuan
authors.initials: XY
authors.lastname: Yang
authors.affiliation: Anyang Eye Hospital, Henan Province, China.
authors.forename: Yi-Peng
authors.initials: YP
authors.lastname: Wang
authors.affiliation: Department of Epidemiology and Health Statistics, Peking University School of Public Health, Beijing, China.
authors.forename: Si-Yan
authors.initials: SY
authors.lastname: Zhan
authors.affiliation: Department of Ophthalmology and Westmead Millennium Institute, Centre for Vision Research, University of Sydney, Sydney, Australia.
authors.forename: Paul
authors.initials: P
authors.lastname: Mitchell
authors.affiliation: Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing, China.
authors.forename: Ningli
authors.initials: N
authors.lastname: Wang
authors.affiliation: School of Optometry & Vision Science and Institute of Health and Biomedical Innovation, Queensland University of Technology, Kelvin Grove, Queensland, Australia.
authors.forename: David A
authors.initials: DA
authors.lastname: Atchison
mesh_terms: D000293:Adolescent; D001251:Astigmatism / Q000453:epidemiology / Q000503:physiopathology; D002648:Child; D002681:China / Q000453:epidemiology; D005260:Female; D006801:Humans; D006956:Hyperopia / Q000453:epidemiology* / Q000503:physiopathology; D008297:Male; D009216:Myopia / Q000453:epidemiology* / Q000503:physiopathology; D012029:Refraction, Ocular / Q000502:physiology*; D012307:Risk Factors
keywords: Epidemiology; Optics and Refraction