title: Component dependent risk factors for ocular parameters in Singapore Chinese children.
abstract: OBJECTIVE
  To examine the risk factors for variations in ocular biometry parameters in Singapore Chinese children, a population with a known high prevalence rate of myopia at an early age.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  Children aged 7 to 9 years (n = 1453) from three schools in Singapore.
  
  
  METHODS
  The children underwent A scan biometry and cycloplegic autorefraction measurements. Questions were asked regarding number of books read per week, night lighting, and parental myopia.
  
  
  METHODS
  Axial length, vitreous chamber depth, lens thickness, anterior chamber depth, refraction, and corneal curvature radius measurements were made.
  
  
  RESULTS
  After controlling for several factors, the axial lengths were found to be longer and vitreous chambers deeper in children who were older, male, read more than two books per week, or taller, and those who had at least one parent who was myopic. In these models, children who read more than two books per week had axial lengths that were 0.17 mm longer and vitreous chambers that were 0.15 mm deeper compared with children who read two or fewer books per week. Anterior chambers were deeper in males and taller children, whereas corneal curvature was steeper in female, older, and shorter children.
  
  
  CONCLUSIONS
  Increases of axial length and vitreous cavity depth were associated with older age, being male, reading more than two books per week, increased height, and parental history of myopia. Of these risk factors, however, neither reading nor parental myopia history were associated with values for anterior chamber depth, corneal curvature, or lens thickness. These findings confirm that conventional risk factors for myopia associated with the vitreous cavity, but suggest that anterior segment parameters such as corneal curvature and lens thickness may be subject to unrelated postnatal growth control mechanisms.
authors.affiliation: Department of Community, Occupational and Family Medicine, National University of Singapore, Singapore, Republic of Singapore. Singapore Eye Research Institute, Singapore, Republic of Singapore. cofsawsm@nus.edu.sg
authors.forename: Seang-Mei
authors.initials: SM
authors.lastname: Saw
authors.forename: Andrew
authors.initials: A
authors.lastname: Carkeet
authors.forename: Kee-Seng
authors.initials: KS
authors.lastname: Chia
authors.forename: Richard A
authors.initials: RA
authors.lastname: Stone
authors.forename: Donald T H
authors.initials: DT
authors.lastname: Tan
mesh_terms: D017677:Age Distribution; D000867:Anterior Chamber / Q000473:pathology; D001699:Biometry; D002648:Child; D002681:China / Q000208:ethnology; D003315:Cornea / Q000473:pathology; D003430:Cross-Sectional Studies; D005123:Eye / Q000473:pathology*; D005260:Female; D006801:Humans; D007908:Lens, Crystalline / Q000473:pathology; D008297:Male; D009216:Myopia / Q000208:ethnology*; D015995:Prevalence; D012029:Refraction, Ocular; D012307:Risk Factors; D017678:Sex Distribution; D012846:Singapore / Q000453:epidemiology; D014822:Vitreous Body / Q000473:pathology