Purpose: Detection and correction of uncorrected refractive errors among 12 million children is an overwhelming task for the 500 currently available eye-care professionals in Nepal. A mid-term review of VISION 2020 goals in Nepal has recommended utilizing alternative human resources that could screen children for visual impairment. This study was conducted to assess the validity of vision screening of school children by trained high school students when compared to optometrist testing as the gold standard.
Methods: A total of 150 students were selected, based on their merit by the headmasters of 25 schools in Nepal and trained for two days by optometrists to screen visual acuity of their peers. Visual acuity ≤ 6/12 in either eye was referred as abnormal vision. A random sample of 1,209 screened students was selected and their visual acuity was reassessed by optometrists under the same settings adopted by trained students. Using optometrist scores as the gold standard, screening results of trained students were analyzed for validity.
Results: Mean age of screened students was 12.2 ± 3.03 years (range: 4-19 years) and 57.4% of them were female. Sensitivity of vision screening test done by trained students was 81.7% and the specificity was 97.6%. A positive predictive value of the test was 77.3% and negative predictive value was 98.2%.
Conclusions: With high sensitivity and specificity values, vision screening done by trained students is effective for screening visual acuity of school children. Countries with limited eye-care professionals and infrastructures can effectively train and utilize students for timely detection of poor vision among children.
Keywords: Student-led vision screening; detection of visual impairment in school children; screening school children for refractive error; sensitivity and specificity; validity of vision screening.