Prevalence and etiology of low vision in children of 5-18 years of age using model of community based door to door screening in an urban slum of Delhi.

Purpose: To study the prevalence and causes of low vision in children 5-18 years of age residing in an urban slum of northern India.

Methods: A prospective observational study between May 2021 and March 2022, where door-to-door (DTD) screening was performed in the chosen slum by trained personnel using PEEK acuity software. Children with visual acuity <6/9 in any eye were subsequently referred to the vision center, where cycloplegic refraction and complete ocular evaluation were done by an optometrist and pediatric ophthalmologist, and glasses were prescribed at the vision center. However, those needing further surgical or medical management were referred to the tertiary institute. After complete intervention, the prevalence of low vision was then calculated, and the most attributable cause of low vision was noted for each child. The complete data was divided into four sub-populations based on four gender-age combinations (male and female, younger and older). The prevalence of children with low vision for each sub-population was calculated separately, and then the results were pooled to estimate the prevalence for the entire population.

Results: Using a DTD screening model, 106,524 children in the age group of 5-18 years were screened. Of these, 54,541 (51.2%) were males. Amongst 7084 children who were referred from DTD screening to the vision center, 5154 children had visual impairment. After all the required interventions were completed, 110 patients were finally considered to have low vision.

Conclusion: The prevalence of low vision in this urban slum was 0.142%. Refractive amblyopia was the major cause of low vision, followed by retinal causes. Identifying low vision early provides families and caregivers with access to appropriate resources, support services, and educational tools that can aid in the child's development.