Accuracy of visual assessment by school teachers in school eye screening program in delhi

Abstract

Background: Although school eye screening is a major activity of the National Program for Control of Blindness, inadequate evidence exists about accuracy of school teachers in screening.

Objectives: Compare quality of referral for subnormal vision by school teachers and primary eye care workers (PECW) in school children and to establish appropriate cutoff for identification of subnormal vision in school going children.

Materials and methods: This was a cross-sectional study involving school children studying in classes 1 to 9 in different schools of Delhi evaluated for sub-normal vision. Vision was recorded by the teacher and a primary eye care worker especially trained for the study using the optotypes of Early treatment Diabetic Retinopathy Survey (ETDRS) vision chart with standard lighting.

Results: The total number of children enlisted in the 20 selected schools was 10,114. Of these, 9838 (97.3%) children were examined in the study. The mean age of children enrolled in the study was 11.6 ± 2.19 years with 6752 (66.9%) males. The sensitivity and specificity of teachers in comparison to PECW using 6/9.5 vision level as cutoff for referral was 79.2% and 93.3%, respectively compared to 77.0% and 97.1%, respectively on using the 6/12 optotype. The results showed significantly higher sensitivity and lower specificity for private schools against government schools and for older against younger children.

Conclusions: Our results show that the use of teachers and shift to use of the 6/12 sized "E" for the school eye screening (SES) program is appropriate and would substantially reduce the work of eye care providers while improving its overall efficiency.

Keywords: Accuracy; national program for control of blindness; refractive errors; school eye screening; sensitivity and specificity.

Figure 1

Flowchart showing the examination of children, the order of test execution and the number of patients undergoing the evaluation and outcome of the test for 6/9.5 vision level as cut-off. The other vision level as cut-off i.e. 6/12 and 6/15 had similar methodology