Prevalence and determinants of visual impairment amongst school-aged children in Southern Nigeria

Background: Visual impairment among school children is relatively common and research provides evidence for integration of comprehensive eye care into school health programmes. Aim: To determine the prevalence and determinants of visual impairment in school-aged children in Southern Nigeria. Setting: School aged children from 10 public and private-owned schools in Cross River State, Southern Nigeria. Methods: This cross-sectional analytic study used a multistage random sampling technique to select 2418 school children aged 6-17 years. Comprehensive eye examinations were performed on the study. The logistic regression analysis with 95% confidence interval (CI) was used to test hypotheses. Results: Of the 2418 school children selected, 2110 (87%) were assessed. The prevalence 'of uncorrected, presenting and best corrected visual acuity of 0.3 (20/40) or worse in the better eye' was 7.3%, 7.2% and 0.19%, respectively. Errors of refraction were the cause of the impairment in 198 (70.7%; 63.5-76.0) eyes with reduced vision, followed by glaucoma suspects 38 (19.2%;13.8-24.8), amblyopia (3.0%; 1.1-6.4) and corneal opacity 3 (1.5%; 0.3-4.3). The major and independent predictors of visual impairment were age (adjusted odds ratio [AOR] 1.97, 95% 1.45-2.67), high socio-economic status (adjusted odds ratio [AOR] 1.68, 95% 1.36-2.09) and female gender (AOR 1.35, 95%1.00-1.88). Conclusion: The common causes of visual impairment in school-aged children are avoidable, and are mostly because of uncorrected refractive error, which could reflect inadequate refractive error services in the area.