Evaluation of Portable, Low-Cost Autorefractor in School Students with Limited Eye Care Access in Northeastern Brazil

Abstract

This study compared the refraction measurements of the ClickCheck™ device (CCD), Topcon KR-8000, and subjective clinical refractometry (SCR) in Brazilian public school students with limited access to eye care. Eighty-seven eyes of healthy students aged 7 to 17 underwent refractometry using the CCD, Topcon KR-8000, and SCR methods under cycloplegia, with only the right-eye data analyzed. For comparison, the measurements were converted into spherical equivalents (SEs) and vector magnitudes. The mean SE difference between CCD and Topcon KR-8000 was −0.27 ± 0.58 (p < 0.0001), while the vector magnitudes at the 90° and 135° meridians were −0.23 ± 0.55 (p = 0.0001) and +0.04 ± 0.47 (p = 0.2246), respectively, demonstrating no clinical relevance. Similarly, the mean SE difference between CCD and SCR was −0.18 ± 0.58 (p = 0.065), with vector magnitudes of −0.20 ± 0.50 (p = 0.0003) at 90° and +0.03 ± 0.46 (p = 0.3730) at 135°, also lacking clinical relevance. Despite statistically significant differences between the methods, the findings confirm strong agreement, validating CCD as an effective refractive assessment tool for children in low-resource settings. These methods can enhance access to refraction services in underserved populations.