title: Prevalence of congenital colour vision deficiency among secondary school students in Ibadan, South-West Nigeria.
abstract: The aim was to determine the prevalence and pattern of congenital colour vision deficiency among secondary school students in Ibadan, Nigeria.
  
  
  
  A descriptive cross-sectional study was conducted among students from three public secondary schools through a multi-staged sampling method. Ocular examination including visual acuity assessment and colour vision test with the Ishihara plate was performed for all students. Further assessment with the Farnsworth-Munsell D-15 panel was performed for those who failed the Ishihara test.
  
  
  
  One thousand six hundred and thirty-five students participated in the study. There were 769 (47.0%) males with mean age of 13.9 ± 1.9 years. The overall prevalence of congenital colour vision deficiency was 2.3% with prevalence of 3.8% and 0.9% in males and females, respectively, which was statistically significant (P = 0.00112), and equal proportion of deutans 11 (32.0%) and protans 12 (35.0%) ratio of 1:1.1.
  
  
  
  The prevalence of congenital colour vision deficiency among public secondary school students in Ibadan is comparable to findings in other parts of the country.
authors.affiliation: Department of Ophthalmology, University College Hospital, Ibadan, Oyo, Nigeria.
authors.forename: Mary Ogbenyi
authors.initials: MO
authors.lastname: Ugalahi
authors.affiliation: Department of Ophthalmology, University of Ibadan, University College Hospital, Ibadan, Oyo, Nigeria.
authors.forename: Oluyemi
authors.initials: O
authors.lastname: Fasina
authors.affiliation: Department of Ophthalmology, University of Ibadan, University College Hospital, Ibadan, Oyo, Nigeria.
authors.forename: Olufunmilola A
authors.initials: OA
authors.lastname: Ogun
authors.affiliation: Ojulowo Eye Centre, Ibadan, Oyo, Nigeria.
authors.forename: Benedictus G K
authors.initials: BG
authors.lastname: Ajayi
mesh_terms: D000293:Adolescent; D002648:Child; D003117:Color Vision Defects / Q000453:epidemiology*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D009549:Nigeria; D015995:Prevalence; D012574:Schools; D013334:Students