Comparison of a Novel Binocular Refraction System with Standard Digital Phoropter Refraction

Abstract

SIGNIFICANCE New refractive technologies are consistently emerging in the optometry market, necessitating validation against current clinical standards. PURPOSE This study aimed to compare the refractive measurements between standard digital phoropter refraction and the Chronos binocular refraction system. METHODS Standardized subjective refraction was conducted on 70 adult participants using two separate refraction systems. The final subjective values from both devices were compared for M, J 0, and J 45. The time taken to complete refraction and patient's comfort were also evaluated. RESULTS Good agreement was found between the standard and Chronos refraction, with narrow mean differences (including 95% confidence intervals) and no significant bias for M (0.03 D, −0.05 to 0.11 D), J 0 (−0.02 D, −0.05 to −0.01 D), and J 45 (−0.01 D, −0.03 to 0.01 D). The bounds of the limits of agreement of M were −0.62 (lower bound; −0.76 to −0.49) and 0.68 (upper bound; 0.54 to 0.81), those of J 0 were −0.24 (lower bound; −0.29 to −0.19) and 0.19 (upper bound; 0.15 to 0.24), and those of J 45 were −0.18 (lower bound; −0.21 to −0.14) and 0.16 (upper bound; 0.12 to 0.19). No significant differences were noted between the two techniques for any of the refraction components (M standard = −3.03 ± 2.42 D, M novel = −3.06 ± 2.37 D, z = 0.07, P = .47; J 0 standard = 0.12 ± 0.40 D, J 0 novel = 0.15 ± 0.41 D, z = 1.32, P = .09; J 45 standard = −0.04 ± 0.19 D, J 45 novel = −0.03 ± 0.19 D, z = 0.50, P = .31). The Chronos was significantly faster than the standard technique, with an average difference of 19 seconds (standard, 190 ± 44 seconds; novel, 171 ± 38 seconds; z = 4.91; P < .001). CONCLUSIONS The final subjective refraction end points of the standard technique and the Chronos were well aligned in this group of adult participants, and no statistically or clinically significant differences were noted in M, J 0, or J 45 components. The Chronos offered improved efficiency, meeting the demands of eye care.