Abstract
Purpose: Refractive error is the most common cause of visual impairment among school children. Worldwide, school vision testing is one major area of thrust to address vision screening among school children, and is carried out by a diverse group of professionals and non-professionals, with variable success rates. In a pilot study we aimed to determine how efficiently and reliably students could self-examine their vision and how many actually seek intervention for refraction and eventually wear glasses.
Methods: The pilot study was done in 25 schools in a rural area of northern India. The methodology of self-assisted vision examination (SAVE) was directly demonstrated to school children. School children self-examined their visual acuity, and sensitivity, specificity and positive and negative predictive values were calculated after secondary screening by professionals. Students requiring refraction were given referral slips. Frequency of uptake of glasses for those referred for refractive services was assessed in a follow-up visit.
Results: A total of 7411 students in 6th to 12th standard were enrolled in the pilot study. Sensitivity and specificity of the SAVE strategy were 96.22% (95% confidence interval [CI] 94.52–97.43%) and 90.23% (95% CI 87.79–92.23%), respectively. The positive predictive value was 90.83% (95% CI 88.55–92.71%) and negative predictive value was 95.95% (95% CI 94.13–97.24%). At the time of follow-up 66% of students had undergone refraction and 81% of these were wearing glasses.
Conclusion: SAVE provides a simple, acceptable and valid alternate strategy for school vision screening. However, factors influencing procurement of glasses and their use will require further study.
Acknowledgements
We acknowledge the valuable support from Mr Sadhuram Jakhar, Principal of Bharti Vidyamandir Barwala for coordination between the research team and schools in conducting this pilot study. We also extend our sincere gratitude to Bharti Education Society, Barwala, Hisar (Haryana) and the District Blindness Control Society for providing free glasses; and to the school authorities, parents and school children for voluntary participation in this study.