Prevalence of undetected refractive errors among school children: a cross sectional study in urban Etawah, India

Neha Sachan, Dhiraj Srivastava, P. K. Jain, Prashant Kumar Bajpai, Santosh Kumar Singh, Jyoti Mehra


Background: Refractive error is the most common cause of blindness which can be corrected easily. Uncorrected refractive errors are responsible for about 19.7% of blindness in India. The aim and objectives of the study were to find out the prevalence of undetected refractive errors in school children and to find out associated factors related to it.

Methods: This was a cross sectional study in which school children studying in class 5th to 11th were included. Vision of all the children was checked by using Snellen’s chart. The responses were recorded on a pre-designed and pre-tested questionnaire. Data entry was done in MS-EXCEL sheet and analysis was done by using SPSS-23.

Results: There are total 350 students out of which 200 (57%) are males and 150 (43%) are females. The undetected refractive error is present in 12% males and 15.3% females. Thus, 47 out of 350 (13.4%) of the children had prevalence of undetected refractive errors.

Conclusions: It is recommended that adequate preschool examination of the children be made mandatory as a part of the admission policy of all the schools. In addition, there should be periodic examination of the school children at least on annual basis.


Undetected refractive error, Blindness, Snellen’s chart

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