title: Characteristics of Astigmatism in a Population of Tunisian School-Children.
abstract: OBJECTIVE
  To evaluate the characteristics of astigmatism in a cross-sectional study of schoolchildren in Tunisia.
  
  
  METHODS
  A random cluster design was used to recruit children from primary schools across urban and rural settings in Tunisia, from 2008 to 2010. A total of 6192 students aged 6-14-years old were enrolled. All students whose uncorrected visual acuity was worse than 20/20 underwent a complete ophthalmic examination. Astigmatism was defined as the cylinder power of 0.75 diopter (D) or greater.
  
  
  RESULTS
  The prevalence of astigmatism was 6.67%. Mean cylinder power was - 1.89 ± 0.79D. The prevalence of astigmatism increased statistically significantly with age (P = 0.032). The prevalence of astigmatism was not significantly related to gender (P = 0.051). Of those with cylinder, 63.6%, 17.8%, and 18.6% schoolchildren had with with-the-rule, against-the-rule, and oblique astigmatism, respectively. ATR astigmatism was significantly higher in males (P = 0.033). There was no significant association between the student's area of residence and astigmatism (P = 0.059).
  
  
  CONCLUSIONS
  Comparisons with other studies show that the prevalence of astigmatism in Tunisia is higher than in some countries. The prevalence of astigmatism increased with age but not gender. The majority of schoolchildren had with-the-rule astigmatism.
authors.affiliation: Department B of Ophthalmology, Hedi Rais Institute of Ophthalmology, Faculty of Medicine of Tunis, University of El Manar, Tunis, Tunisia.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Chebil
authors.affiliation: Department B of Ophthalmology, Hedi Rais Institute of Ophthalmology, Faculty of Medicine of Tunis, University of El Manar, Tunis, Tunisia.
authors.forename: Lina
authors.initials: L
authors.lastname: Jedidi
authors.affiliation: Department B of Ophthalmology, Hedi Rais Institute of Ophthalmology, Faculty of Medicine of Tunis, University of El Manar, Tunis, Tunisia.
authors.forename: Nibrass
authors.initials: N
authors.lastname: Chaker
authors.affiliation: Department B of Ophthalmology, Hedi Rais Institute of Ophthalmology, Faculty of Medicine of Tunis, University of El Manar, Tunis, Tunisia.
authors.forename: Fedra
authors.initials: F
authors.lastname: Kort
authors.affiliation: Department B of Ophthalmology, Hedi Rais Institute of Ophthalmology, Faculty of Medicine of Tunis, University of El Manar, Tunis, Tunisia.
authors.forename: Rym
authors.initials: R
authors.lastname: Limaiem
authors.affiliation: Department B of Ophthalmology, Hedi Rais Institute of Ophthalmology, Faculty of Medicine of Tunis, University of El Manar, Tunis, Tunisia.
authors.forename: Fatma
authors.initials: F
authors.lastname: Mghaieth
authors.affiliation: Department B of Ophthalmology, Hedi Rais Institute of Ophthalmology, Faculty of Medicine of Tunis, University of El Manar, Tunis, Tunisia.
authors.forename: Leila
authors.initials: L
authors.lastname: El Matri
mesh_terms: D000293:Adolescent; D001251:Astigmatism / Q000453:epidemiology*; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D015995:Prevalence; D012424:Rural Population / Q000706:statistics & numerical data*; D012574:Schools; D014416:Tunisia / Q000453:epidemiology; D014505:Urban Population / Q000706:statistics & numerical data*; D014792:Visual Acuity / Q000502:physiology
keywords: Astigmatism; Prevalence; Schoolchildren; Tunisia