title: Near Work Related Parameters and Myopia in Chinese Children: the Anyang Childhood Eye Study.
abstract: OBJECTIVE
  To examine the associations of near work related parameters with spherical equivalent refraction and axial length in Chinese children.
  
  
  METHODS
  A total of 1770 grade 7 students with mean age of 12.7 years were examined with cycloplegic autorefraction and axial length. Questions were asked regarding time spent in near work and outdoors per day, and near work related parameters.
  
  
  RESULTS
  Multivariate models revealed the following associations with greater odds of myopia: continuous reading (> 45min), odds ratio [OR], 1.4; 95% confidence interval [CI], 1.1-1.8; close television viewing distance (≤ 3m), OR, 1.7; 95% CI, 1.2-2.3; head tilt when writing, OR, 1.3; 95% CI, 1.1-1.7, and desk lighting using fluorescent vs. incandescent lamp, OR, 1.5; 95% CI, 1.2-2.0. These factors, together with close reading distance and close nib-to-fingertip distance were significantly associated with greater myopia (P<0.01). Among near work activities, only reading more books for pleasure was significantly associated with greater myopia (P=0.03). Television viewing distance (≤ 3 m), fluorescent desk light, close reading distance (≤20 cm) and close nib-to-fingertip distance (≤ 2 cm) were significantly associated with longer axial length (P<0.01). Reading distance, desk light, and reading books for pleasure had significant interaction effects with parental myopia.
  
  
  CONCLUSIONS
  Continuous reading, close distances of reading, television viewing and nib-to-fingertip, head tilt when writing, reading more books for pleasure and use of fluorescent desk light were significantly associated with myopia in 12-year-old Chinese children, which indicates that visual behaviors and environments may be important factors mediating the effects of near work on myopia.
authors.affiliation: Beijing Tongren Eye Center, Beijing Tongren Hospital, Beijing Ophthalmology Visual Science Key Lab, Beijing Institute of Ophthalmology, Capital Medical University, Beijing, China.
authors.forename: Shi-Ming
authors.initials: SM
authors.lastname: Li
authors.affiliation: Beijing Tongren Eye Center, Beijing Tongren Hospital, Beijing Ophthalmology Visual Science Key Lab, Beijing Institute of Ophthalmology, Capital Medical University, Beijing, China.
authors.forename: Si-Yuan
authors.initials: SY
authors.lastname: Li
authors.affiliation: Beijing Tongren Eye Center, Beijing Tongren Hospital, Beijing Ophthalmology Visual Science Key Lab, Beijing Institute of Ophthalmology, Capital Medical University, Beijing, China.
authors.forename: Meng-Tian
authors.initials: MT
authors.lastname: Kang
authors.affiliation: Beijing Tongren Eye Center, Beijing Tongren Hospital, Beijing Ophthalmology Visual Science Key Lab, Beijing Institute of Ophthalmology, Capital Medical University, Beijing, China.
authors.forename: Yuehua
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Anyang Eye Hospital, Anyang, Henan Province, China.
authors.forename: Luo-Ru
authors.initials: LR
authors.lastname: Liu
authors.affiliation: Anyang Eye Hospital, Anyang, Henan Province, China.
authors.forename: He
authors.initials: H
authors.lastname: Li
authors.affiliation: Anyang Eye Hospital, Anyang, 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: Centre for Vision Research, Department of Ophthalmology and Westmead Millennium Institute, University of Sydney, Sydney, Australia.
authors.forename: Bamini
authors.initials: B
authors.lastname: Gopinath
authors.affiliation: Centre for Vision Research, Department of Ophthalmology and Westmead Millennium Institute, University of Sydney, Sydney, Australia.
authors.forename: Paul
authors.initials: P
authors.lastname: Mitchell
authors.affiliation: Beijing Tongren Eye Center, Beijing Tongren Hospital, Beijing Ophthalmology Visual Science Key Lab, Beijing Institute of Ophthalmology, Capital Medical University, Beijing, China.
authors.forename: Ningli
authors.initials: N
authors.lastname: Wang
mesh_terms: D000293:Adolescent; D044466:Asian People / Q000706:statistics & numerical data; D002648:Child; D002681:China; D005123:Eye / Q000473:pathology / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D015999:Multivariate Analysis; D009216:Myopia / Q000175:diagnosis* / Q000208:ethnology / Q000503:physiopathology; D011932:Reading; D012029:Refraction, Ocular / Q000502:physiology; D011795:Surveys and Questionnaires; D013690:Television; D013997:Time Factors; D014937:Work