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Updated: May 9, 2026

Subjective Refraction Test Using a Smartphone for Vision Screening
Published on: October 18, 2024
[Refractive errors among schoolchildren in the central region of Togo]
K B Nonon Saa1, K Atobian, M Banla
1Ministère de la Santé, université de Lomé, faculté mixte de médecine et de pharmacie Lomé, BP 1515, Lomé, Togo.
Abstract:
Untreated refractive errors represent the main visual impairment in the world but also the easiest to avoid. The goal of this survey is to use clinical and epidemiological data to efficiently plan distribution of corrective glasses in a project supported by the Swiss Red Cross in the central region of Togo. To achieve this goal, 66 primary schools were identified randomly in the catchment area of the project. The teachers at these schools were previously trained to test visual acuity (VA). The schoolchildren referred by these teachers were examined by eye care professionals. The schoolchildren with ametropia (VA≤7/10 in at least one eye) underwent cycloplegic autorefraction. Of a total of 19,252 registered schoolchildren, 13,039 underwent VA testing by the teachers (participation rate=68%). Among them, 366 cases of ametropia were identified (prevalence about 3%). The average age of the schoolchildren examined was 10.7±2.3years, with a sex ratio of 1.06. Autorefraction, which was performed for 37% of the schoolchildren with ametropia allowed them to be classified into three groups: hyperopia (4%), myopia (5%) and astigmatism of all types (91%). Regardless of the type of ametropia, the degree of severity was mild in 88%. The results of this survey have highlighted the importance of the teachers' contribution to eye care education in the struggle against refractive errors within the school environment, as well as helping to efficiently plan actions against ametropia.
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