title: Corneal curvature radius and associated factors in Chinese children: the Shandong Children Eye Study.
abstract: OBJECTIVE
  To investigate the distribution of the (CCR) and its associated factors in children.
  
  
  METHODS
  Using a random cluster sampling method, the school-based, cross-sectional Shandong Children Eye Study included children aged 4 to 18 years from the rural county of Guanxian and the city of Weihai in the province of Shandong in East China. CCR was measured by ocular biometry.
  
  
  RESULTS
  CCR measurements were available for 5913 (92.9%) out of 6364 eligible children. Mean age was 10.0±3.3 years, and mean CCR was 7.84±0.27 mm (range: 6.98 to 9.35 mm). In multivariate linear regression analysis, longer CCR (i.e. flatter cornea) was significantly associated with the systemic parameters of male sex (P<0001; standardized regression coefficient beta: -0.08; regression coefficient B: -0.04; 95% Confidence Interval (CI): -0.05, -0.03), younger age (P<0.001; beta: -0.37; B: -0.03; 95%CI: -0.04, -0.03), taller body height (P = 0.002; beta: 0.06; B: 0.001; 95%CI: 0.000, 0.001), lower level of education of the father (P = 0.001; beta: -0.04; B: -0.01; 95%CI: -0.02, -0.01) and maternal myopia (P<0.001; beta: -0.07; B: -0.04; 95%CI: -0.06, -0.03), and with the ocular parameters of longer ocular axial length (P<0.001; beta: 0.59; B: 0.13; 95%CI: 0.12, 0.14), larger horizontal corneal diameter (P<0.001; beta: 0.19; B: 0.13; 95%CI: 0.11, 0.14), and smaller amount of cylindrical refractive error (P = 0.001; beta: -0.09; B: -0.05; 95%CI: -0.06, -0.04).
  
  
  CONCLUSIONS
  Longer CCR (i.e., flatter corneas) (mean:7.84±0.27 mm) was correlated with male sex, younger age, taller body height, lower paternal educational level, maternal myopia, longer axial length, larger corneas (i.e., longer horizontal corneal diameter), and smaller amount of cylindrical refractive error. These findings may be of interest for elucidation of the process of emmetropization and myopization and for corneal refractive surgery.
authors: The First College of Clinical Medicine, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China; Institute of Basic Medicine, Shandong Academy of medical sciences, Jinan, Shandong, China.
authors: Yue Ying
authors: YY
authors: Zhang
authors: Eye Institute of Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China.
authors: Wen Jun
authors: WJ
authors: Jiang
authors: Department of Ophthalmology, Wulian People's Hospital, Rizhao, Shandong, China.
authors: Zhao E
authors: ZE
authors: Teng
authors: Department of Ophthalmology, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China.
authors: Jian Feng
authors: JF
authors: Wu
authors: Department of Ophthalmology, The Second Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan Shandong, China.
authors: Yuan Yuan
authors: YY
authors: Hu
authors: Department of Ophthalmology, The Second Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan Shandong, China.
authors: Tai Liang
authors: TL
authors: Lu
authors: Eye Institute of Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China.
authors: Hui
authors: H
authors: Wu
authors: Department of Ophthalmology, The Second Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan Shandong, China.
authors: Wei
authors: W
authors: Sun
authors: Eye Institute of Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China; Department of Ophthalmology, The Second Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan Shandong, China.
authors: Xing Rong
authors: XR
authors: Wang
authors: Eye Institute of Shandong University of Traditional Chinese Medicine, Jinan, Shandong, China; Department of Ophthalmology, The Second Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan Shandong, China.
authors: Hong Sheng
authors: HS
authors: Bi
authors: Department of Ophthalmology, Medical Faculty Mannheim of the Ruprecht-Karls-University Heidelberg, Germany.
authors: Jost B
authors: JB
authors: Jonas
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D002681:China; D003315:Cornea / Q000033:anatomy & histology*; D005123:Eye / Q000033:anatomy & histology*; D005260:Female; D006801:Humans; D008297:Male; D012030:Refractive Errors / Q000473:pathology*