title: Effect of uncorrection versus full correction on myopia progression in 12-year-old children.
abstract: OBJECTIVE
  To investigate the effects of no correction versus full correction on myopia progression in Chinese children over a period of 2 years.
  
  
  METHODS
  Myopia was defined as cycloplegic spherical equivalent (SE) of ≤ -0.50 D. Uncorrection was defined as no spectacles worn, and full correction was defined as when the value of SE subtracted from the dioptric power of the child's current spectacles was less than 0.5 D. Ocular examinations included visual acuity, cycloplegic autorefraction, axial length and vertometer measurements. Questionnaires were completed by parents on behalf of the children.
  
  
  RESULTS
  A total of 121 myopic children, with a median age of 12.7 years, were screened from the Anyang Childhood Eye Study, with 65 in the uncorrected group and 56 in the full correction group. At 2-year follow-up, children with no correction had slower myopia progression (-0.75 ± 0.49 D vs. -1.04 ± 0.49 D, P < 0.01) and less axial elongation (0.45 ± 0.18 mm vs. 0.53 ± 0.17 mm, P = 0.02) than children with full correction. In multivariate modeling, adjusting for baseline SE or axial length, age, gender, height, number of myopic parents, age at myopia onset, and time spent in near work and outdoors, children with no correction still had slower myopia progression (-0.76 ± 0.07 vs. -1.03 ± 0.08 D, P < 0.01) and less axial elongation (0.47 ± 0.03 mm vs. 0.51 ± 0.03 mm, P < 0.01). Myopia progression decreased significantly with an increasing amount of undercorrection in all children (r = 0.22, b = 0.16, P = 0.01).
  
  
  CONCLUSIONS
  Our findings suggest that myopic defocus slows the progression of myopia in already myopic children, supporting previous findings from animal studies.
authors: Beijing Tongren Eye Center, Beijing Tongren Hospital, Beijing Ophthalmology & Visual Science Key Lab, Beijing Institute of Ophthalmology, Capital Medical University, Beijing, China, 100730.
authors: Yun-Yun
authors: YY
authors: Sun
authors: Beijing Tongren Eye Center, Beijing Tongren Hospital, Beijing Ophthalmology & Visual Science Key Lab, Beijing Institute of Ophthalmology, Capital Medical University, Beijing, China, 100730. lishiming81@163.com.
authors: Shi-Ming
authors: SM
authors: Li
authors: Department of Ophthalmology, Beijing Children's Hospital, Capital Medical University, Beijing, China.
authors: Si-Yuan
authors: SY
authors: Li
authors: Beijing Tongren Eye Center, Beijing Tongren Hospital, Beijing Ophthalmology & Visual Science Key Lab, Beijing Institute of Ophthalmology, Capital Medical University, Beijing, China, 100730.
authors: Meng-Tian
authors: MT
authors: Kang
authors: Anyang Eye Hospital, Anyang, Henan Province, China.
authors: Luo-Ru
authors: LR
authors: Liu
authors: Department of Epidemiology and Health Statistics, Peking University School of Public Health, Beijing, China.
authors: Bo
authors: B
authors: Meng
authors: Beijing Tongren Eye Center, Beijing Tongren Hospital, Beijing Ophthalmology & Visual Science Key Lab, Beijing Institute of Ophthalmology, Capital Medical University, Beijing, China, 100730.
authors: Feng-Ju
authors: FJ
authors: Zhang
authors: School of Optometry and Vision Sciences, Cardiff University, Cardiff, UK.
authors: Michel
authors: M
authors: Millodot
authors: Beijing Tongren Eye Center, Beijing Tongren Hospital, Beijing Ophthalmology & Visual Science Key Lab, Beijing Institute of Ophthalmology, Capital Medical University, Beijing, China, 100730. wningli@vip.163.com.
authors: Ningli
authors: N
authors: Wang
mesh_terms: D000065:Accommodation, Ocular / Q000502:physiology*; D058452:Axial Length, Eye; D002648:Child; D018450:Disease Progression; D005139:Eyeglasses; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009216:Myopia / Q000503:physiopathology / Q000628:therapy*; D012029:Refraction, Ocular / Q000502:physiology*; D011795:Surveys and Questionnaires; D013997:Time Factors; D014792:Visual Acuity
keywords: Children; Full correction; Myopia progression; Myopic defocus; Uncorrection