title: Prevalence and causes of visual impairment among Saudi adults attending primary health care centers in northern Saudi Arabia.
abstract: OBJECTIVE
  Few studies have been conducted in Saudi Arabia to estimate the prevalence of visual impairment and its causes. The objective of this study was to estimate the prevalence of visual impairment, and identify its causes and associated factors among the adult population attending primary health care (PHC) centers in Aljouf province, in northern Saudi Arabia.
  
  
  METHODS
  A cross-sectional study during the year 2005 in PHC centers in Aljouf province in northern Saudi Arabia.
  
  
  METHODS
  A sample of 620 Saudi adults, of age 18 years and older, from the catchment area of the Aljouf PHC centers, were randomly selected through a multistage random sampling technique. Data were collected using a questionnaire about socioeconomic and related information and a visual acuity test was performed using the Snellen chart (E). Diagnosis was established according to World Health Organization (WHO) criteria. Visual impairment was categorized into blindness for a visual acuity of less than 3/60 (20/400, 0.05) in the better eye with the best correction and low vision for a best corrected visual acuity of less than 6/18 (20/60, 0.3) but not less than 3/60 (20/400, 0.05) in the better eye. Regression analysis was used to identify the predictors of visual impairment.
  
  
  RESULTS
  Of 617 adult Saudis interviewed and examined, 269 (43.6%) were females. The mean (SD) age was 38.6 (16.2) years. The overall prevalence of visual impairment was 13.9% (95% CI: 11.4%-16.9%). The main medical causes of visual impairments were refractive errors (36.0%) followed by cataract (29.1%) and diabetic retinopathy (20.9%), and the least leading cause was glaucoma (5.8%). The most prominent determinants of visual impairment were age (P<.05), sex (P<.001), and a history of previous eye injury (P<.05).
  
  
  CONCLUSIONS
  Prevalence of visual impairment in the study population from the Aljouf area is high. It is recommended that regular checks of visual acuity be conducted for all Saudis of age 50+ years, who attend the PHC centers.
authors.affiliation: Directorate of Primary Health Care, Aljouf, Saudi Arabia.
authors.forename: Farhan Fayez
authors.initials: FF
authors.lastname: Al-Shaaln
authors.forename: Marwan Abdurrahman
authors.initials: MA
authors.lastname: Bakrman
authors.forename: Adel Mohammad
authors.initials: AM
authors.lastname: Ibrahim
authors.forename: Abdullah Srour
authors.initials: AS
authors.lastname: Aljoudi
mesh_terms: D000328:Adult; D000367:Age Factors; D001766:Blindness / Q000453:epidemiology* / Q000209:etiology; D003430:Cross-Sectional Studies; D005128:Eye Diseases / Q000453:epidemiology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011320:Primary Health Care; D012044:Regression Analysis; D012529:Saudi Arabia / Q000453:epidemiology; D012737:Sex Factors; D012959:Socioeconomic Factors; D011795:Surveys and Questionnaires; D015354:Vision, Low / Q000453:epidemiology* / Q000209:etiology; D014792:Visual Acuity