title: Association of Socio-Economic Status and Visual Impairment: A Population-Based Study in Iran.
abstract: BACKGROUND
  To assess the role of socio-economic inequality in visual impairment (VI) in Varamin district, Iran.
  
  
  METHODS
  Using multistage cluster sampling method, 60 clusters (each with 50 subjects) were recruited and underwent clinical eye examinations. Socio-economic status (SES) was identified based on education, occupation, family assets and housing conditions that were measured at the participants' households using a semi-structured questionnaire and a two-step cluster analysis model. In addition, principal component analysis and the concentration index were used to identify the gap between high and low SES groups.
  
  
  RESULTS
  Participants were categorized in high (522, 24.4%), moderate (974, 43.1%) and low (763, 33.7%) socio-economic levels. In these levels, the prevalence of VI was 5.9% (95% CI: 3.3 to 8.6), 10.4% (95% CI: 8.4 to 12.4), and 12.6% (95% CI: 10.1 to 15.1), respectively. The prevalence of VI in people with low SES was significantly greater than those in high SES level. The proportions of avoidable causes were relatively high in all SES levels (more than 80%) with no significant difference between different levels.
  
  
  CONCLUSIONS
  There is significant inequality in VI prevalence in Varamin district. Avoidable causes are high in all SES groups. Therefore, community-based modalities and preventive programs with a specific notice to poorer SES groups are recommended to improve eye health in this district.
authors.affiliation: Center for Global Health, Department of Public Health, Aarhus University, Denmark, Ophthalmic Epidemiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Marzieh
authors.initials: M
authors.lastname: Katibeh
authors.affiliation: Ophthalmic Epidemiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Zhale
authors.initials: Z
authors.lastname: Rajavi
authors.affiliation: Department of Epidemiology and Biostatistics, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Yaseri
authors.affiliation: Ophthalmic Epidemiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Simin
authors.initials: S
authors.lastname: Hosseini
authors.affiliation: Ophthalmic Epidemiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Sara
authors.initials: S
authors.lastname: Hosseini
authors.affiliation: Ophthalmic Epidemiology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Shadi
authors.initials: S
authors.lastname: Akbarian
authors.affiliation: Department of Community Medicine, Kashan University of Medical Sciences, Kashan, Iran.
authors.forename: Mojtaba
authors.initials: M
authors.lastname: Sehat
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007492:Iran; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D012923:Social Class; D011795:Surveys and Questionnaires; D014786:Vision Disorders / Q000453:epidemiology*