Cycloplegic refraction in preschool children: comparisons between the hand-held autorefractor, table-mounted autorefractor and retinoscopy.

ABSTRACT

AIMS: It is common for refraction to be measured using different testing methods in children, with much debate still ongoing on the preferred method. Therefore, we compared cycloplegic refraction measurements using three objective methods in a large cohort of children. METHODS: We present the findings from a total of 51 children who were recruited and examined as part of the Strabismus, Amblyopia and Refractive error in Singapore preschool children (STARS) study. Each child underwent a comprehensive eye examination, which included cycloplegic refraction using a hand-held autorefractor (Retinomax), a table mounted autorefractor (Canon FK-1) and streak retinoscopy. Spherical equivalent (SE) was calculated as (sphere + half of minus cylinder) and astigmatism was determined using the negative cylindrical component. RESULTS: The current study sample consisted of 29 boys and 22 girls aged between 24 and 72 months (mean age 52.3 months). The mean spherical equivalent (SE) using the table-mounted autorefractor (1.03 +/- 1.64 D) was not significantly different from the streak retinoscopy (1.09 +/- 1.58 D, p = 0.66). However, the mean SE using the hand-held Retinomax (0.80 +/- 1.43 D) was significantly different (more 'minus'p = 0.0004) to streak retinoscopy. The astigmatism measured using the hand held (-0.89 +/- 0.51 D) and table-mounted autorefractor (-0.83 +/- 0.61 D) were significantly greater than that obtained with streak retinoscopy (-0.58 +/- 0.56, p = 0.0003). CONCLUSIONS: The table-mounted autorefractor provided a reading more similar to that of streak retinoscopy than to that of the hand-held autorefractor. However, there were only small differences in mean SE (<0.32 D) between the hand-held Retinomax and the other methods, which will have implications in research investigations of refractive error.