Change in community-based preschool vision screening from visual charts to Retinomax

Abstract

To determine the difference in referral rate and positive predictive values between a community-based vision screening program using eye charts against one using autorefraction. 5,186 preschool children were screened in the 2010-2011 using vision charts, motility, and cover-uncover testing. Follow-up on referred children was determined through provider surveys. 1,773 preschool children were screened in 2011-2012 using autorefraction with Retinomax (manufactured by Nikon, Tokyo, Japan), Hirschberg and cover-uncover testing. Follow-up on referred children was provided on a mobile eye-van. Populations were compared for referral rates and positive predictive value. Positive cases were defined as: refractive error treated with glasses, strabismus, cataracts, or amblyopia. The visual charts screening program referred 4.3% of screened children. The autorefraction screening program referred 16.5% of screened children. The difference (12.2%) was significant (P < 0.0001). The probability of a referred child meeting case definition at follow-up was 69.3% and 56.2% for vision charts and autorefraction, respectively (P = 0.07). A significantly larger number of preschool children were referred for follow-up in a community-based screening program using autorefraction rather than vision charts. There is a non-significant trend towards decreased positive-predictive value in children referred based on Retinomax compared with visual eye chart. Screening programs based on Retinomax are likely to refer a greater number of children that require glasses compared with vision charts. This will increase the number of children appropriately treated with glasses as well as overall screening costs.