title: Visual impairment and spectacle coverage rate in Baoshan district, China: population-based study.
abstract: BACKGROUND
  To investigate the prevalence and risk factors of visual impairment associated with refractive error and the unmet need for spectacles in a special suburban senior population in Baoshan District of Shanghai, one of several rural areas undergoing a transition from rural to urban area, where data of visual impairment are limited.
  
  
  METHODS
  The study was a population based survey of 4545 Chinese aged (age: >60 years or older ) at Baoshan, Shanghai, in 2009. One copy of questionnaire was completed for each subject. Examinations included a standardized refraction and measurement of presenting and best corrected visual acuity (BCVA) as well as tonometry, slit lamp biomicroscopy, and fundus photography.
  
  
  RESULTS
  The prevalence of mild (6/12 to 6/18), moderate (6/18 to 6/60) and severe visual impairment was 12.59%, 8.38% and 0.44%, respectively, and 5.26%, 3.06% and 0.09% with refractive correction. Visual impairment was associated with age, gender, education and career, but not insurance . The prevalence of correctable visual impairment was 5.81% (using 6/18 cutoff) and 13.18% (using 6/12 cutoff). Senior people and women were significantly at a higher risk of correctable visual impairment, while the well-educated on the contrary. The prevalence of undercorrected refractive error (improves by 2 or more lines with refraction) was 24.84%, and the proportion with undercorrected refractive error for mild, moderate , severe and no visual impairment was 61.54%, 67.98%, 60.00% and 14.10%, respectively. The spectacle coverage rate was 44.12%. Greater unmet need for spectacles was observed among elderly people, females, non-peasant, and subjects with less education and astigmatism only.
  
  
  CONCLUSIONS
  High prevalence of visual impairment, visual impairment alleviated by refractive correction, and low spectacle coverage existed among the senior population in Baoshan District of Shanghai. Education for the public of the importance of regular examination and appropriate and accessible refraction service might be helpful to solve the problem.
authors.affiliation: Shanghai Eye Disease Prevention and Treatment Center, No.380, Kangding Road, Jingan, Shanghai 20040, China.
authors.forename: Mengjun
authors.initials: M
authors.lastname: Zhu
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Tong
authors.forename: Rong
authors.initials: R
authors.lastname: Zhao
authors.forename: Xiangui
authors.initials: X
authors.lastname: He
authors.forename: Huijuan
authors.initials: H
authors.lastname: Zhao
authors.forename: Meiling
authors.initials: M
authors.lastname: Liu
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Zhu
mesh_terms: D000368:Aged; D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D005139:Eyeglasses / Q000706:statistics & numerical data*; D005260:Female; D006301:Health Services Needs and Demand; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012030:Refractive Errors / Q000150:complications*; D012307:Risk Factors; D011795:Surveys and Questionnaires; D014507:Urbanization; D014786:Vision Disorders / Q000453:epidemiology* / Q000209:etiology