Vision Impairment among Children in South India: Results from a Large-Scale School Eye Screening.

Purpose: To provide the prevalence of vision impairment and blindness among 250,000 school children aged 6 to 17 years, screened in Tamil Nadu, India.

Methods: The study was conducted between 2016 and 2019 as a part of the school eye screening program in Kanchipuram district, Tamil Nadu. The clinical examination included basic vision testing, objective refraction, subjective acceptance, spectacle dispensing, and a posterior segment evaluation. The prevalence of vision impairment, blindness, low vision, and the association with other demographic variables using logistic regression were calculated.

Results: A total of 250,052 children were screened in 1047 schools and the prevalence of vision impairment, blindness, and low vision in Kanchipuram district was 3.83%, 0.01%, 0.19%, respectively. The major causes for vision impairment, blindness, and low vision were refractive errors (3.05%), high myopia (0.002%), and refractive amblyopia (0.04%), respectively. Vision impairment was significantly associated with urban location (OR = 1.42, 95% CI 1.36-1.48, p < .0001), females (OR = 1.11, 95%CI - 1.08-1.15, p < .0001), private schools (OR = 2.43, 95%CI - 2.35-2.42, p < .0001), higher secondary class grade (OR = 1.69, 95%CI - 1.61-1.77, p = .001), high-school class grade (OR = 1.65, 95%CI - 1.58-1.72, p = .001) and middle school class grade (OR = 1.53, 95%CI - 1.47-1.59, p = .001).

Conclusion: This large-scale school eye screening reports a comparatively lower prevalence of vision impairment, blindness, and low vision when compared to other studies conducted around the world. Although the overall prevalence is relatively low, the causes are mostly refractive. Urban, female, private school-going children aged 11-17 are at higher risk.