Development and Validation of a Screening Tool for The Identification of Refractive Errors Among School Going Children In Tamil Nadu, India


  • Sudharsan V ICMR- National Institute of Epidemiology, Tirunelveli, Tamil Nadu, India
  • Prateeksha Dawn Davidson ICMR- National Institute of Epidemiology, Tirunelveli, Tamil Nadu, India
  • Lakshmi Kandhan V ICMR- National Institute of Epidemiology, Tirunelveli, Tamil Nadu, India
  • Amudha VP Tirunelveli Medical College and Hospital, Tirunelveli, Tamil Nadu, India
  • Rita Hepsi Rani M Tirunelveli Medical College and Hospital, Tirunelveli, Tamil Nadu, India



school children, validation, refractive error, screening tool


Background: The inability to focus light onto the retina, known as refractive error, is a significant cause of correctable visual impairment. Unfortunately, students' ocular complaints often go unnoticed due to a lack of awareness. To address this issue, a questionnaire with high sensitivity and reasonable specificity was developed for teachers to identify students with refractive error.

Methods: A questionnaire with surrogate indicators for refractive error in children was used and the data was analysed using SPSS. Significant markers were scored and a ROC curve determined a suitable cut-off. Sensitivity and specificity were calculated based on this cut-off.

Results: The questionnaire was developed using five variables that had a 65% probability of identifying refractive error, including copying errors, copying from peers, eye squeezing, previous use of glasses, and eye deviation. A cut-off score of 5.5 out of 14 achieved 90% sensitivity and 50% specificity in detecting refractive errors.

Conclusion: This study created a tool with five markers that demonstrated good internal consistency and content validity, it had an average sensitivity and specificity of 84% and 63%, respectively. The tool is twice as likely to identify someone with refractive error than someone without it.


Solebo, A. L., Teoh, L., & Rahi, J. (2017a). Epidemiology of blindness in children. Archives of Disease in Childhood, 102(9), 853-857. Doi: PMid:28465303

Pascolini, D., & Mariotti, S. P. (2011a). Global Estimates of Vis-ual Impairment: 2010. British Journal of Ophthalmology, 96(5), 614-618. Doi: PMid:22133988

Resnikoff, S. (2008) 'Global magnitude of visual impairment caused by uncorrected refractive errors in 2004', Bulletin of the World Health Organization, 86(1), pp. 63-70. Doi: PMid:18235892 PMCid:PMC2647357

Atkinson, J., Anker, S., Nardini, M., Braddick, O., Hughes, C., Rae, S., Wattam-Bell, J., & Atkinson, S. (2002a). Infant vision screening predicts failures on motor and cognitive tests up to school age. Strabismus, 10(3), 187-198. Doi: PMid:12461713

Ipe A, Shibu P, Skariah R. Prevalence of refractive errors and the extent of correction possible with conservative methods, among patients visiting a tertiary care hospital in South Kera-la. Age. 2016;6(15):16-45.

Reichman, N. E., Corman, H., & Noonan, K. (2007a). Impact of child disability on the family. Maternal and Child Health Journal, 12(6), 679-683. Doi: PMid:18060488

Bourne, R. R., Dineen, B. P., Huq, D. M., Ali, S. M., & Johnson, G. J. (2004a). Correction of refractive error in the adult popula-tion of Bangladesh: Meeting the unmet need. Investigative Opthalmology & Visual Science, 45(2), 410. Doi: PMid:14744879

Singh, S., Singh, H., & Joshi, V. S. (1974). Eye diseases among primary school children. Indian Journal of Ophthalmology, 22(3), 1-3.

Maduka-Okafor, F. C., Okoye, O., Ezegwui, I., Oguego, N. C., Okoye, O. I., Udeh, N., Aghaji, A. E., Nwobi, E., Aneji, C., On-wasigwe, E., & Umeh, R. E. (2021). Refractive error and visual impairment among school children: Result of a South-eastern Nigerian Regional Survey. Clinical Ophthalmology, 2021;15: 2345-2353. Doi: PMid:34113078 PMCid:PMC8187082

T Taber, K. S. (2017a). The use of Cronbach's alpha when de-veloping and Reporting Research Instruments in science edu-cation. Research in Science Education, 48(6), 1273-1296. Doi:

Rodrigues, I. B., Adachi, J. D., Beattie, K. A., & MacDermid, J. C. (2017). Development and validation of a new tool to measure the facilitators, barriers and preferences to exercise in people with osteoporosis. BMC Musculoskeletal Disorders, 18(1). Doi: PMid:29258503 PMCid:PMC5738121

Shi J, Mo X, Sun Z. [Content validity index in scale develop-ment]. Zhong Nan Da XueXueBao Yi Xue Ban. 2012 Feb;37(2):152-5. Chinese. DOI: 10.3969/j.issn.1672-7347.2012.02.007

Yamada, J., Stevens, B., Sidani, S., Watt-Watson, J., & de Silva, N. (2010). Content validity of a process evaluation checklist to measure intervention implementation fidelity of the EPIC in-tervention. Worldviews on evidence-based nursing, 7(3), 158-164. Doi: PMid:20180940

Patrick, D. L., Burke, L. B., Gwaltney, C. J., Leidy, N. K., Martin, M. L., Molsen, E., & Ring, L. (2011). Content validity-establishing and reporting the evidence in newly developed patient-reported outcomes (PRO) instruments for Medical Product Evaluation: ISPOR Pro Good Research Practices Task Force Report: Part 2-assessing respondent understanding. Value in Health, 14(8), 978-988. Doi: PMid:22152166

Polit, D. F., & Beck, C. T. (2006). The content validity index: Are you sure you know what's being reported? critique and recommendations. Research in Nursing & Health, 29(5), 489-497. Doi: PMid:16977646

Justice, A. C., Rabeneck, L., Hays, R. D., Wu, A. W., & Bozzette, S. A. (1999). Sensitivity, specificity, reliability, and clinical valid-ity of provider-reported symptoms: a comparison with self-reported symptoms. Outcomes Committee of the AIDS Clini-cal Trials Group. Journal of acquired immune deficiency syn-dromes (1999), 21(2), 126-133.

Ranganathan, P., & Aggarwal, R. (2018). Understanding the properties of diagnostic tests - part 2: Likelihood ratios. Per-spectives in Clinical Research, 9(2), 99. Doi: PMid:29862204 PMCid:PMC5950618

Ranganathan, P., & Aggarwal, R. (2018a). Common pitfalls in statistical analysis: Understanding the properties of diagnos-tic tests - part 1. Perspectives in Clinical Research, 9(1), 40. Doi: PMid:29430417 PMCid:PMC5799952

Deeks, J. J., & Altman, D. G. (2004). Diagnostic tests 4: Likeli-hood ratios. BMJ, 329(7458), 168-169. Doi: PMid:15258077 PMCid:PMC478236




How to Cite

V S, Davidson PD, V LK, Amudha VP, M RHR. Development and Validation of a Screening Tool for The Identification of Refractive Errors Among School Going Children In Tamil Nadu, India. Natl J Community Med [Internet]. 2023 Sep. 1 [cited 2023 Sep. 25];14(09):581-7. Available from:



Original Research Articles