Comparison of refractive value and pupil size under monocular and binocular conditions between the Spot Vision Screener and binocular open-field autorefractor.

We determined the repeatability-reproducibility of refraction values and pupil size measured using the Spot Vision Screener and compare the obtained values with those measured using the binocular open-field autorefractor Grand Seiko WAM 5500 in healthy adults. This cross-sectional study included 22 eyes of 22 healthy adults with emmetropia to myopia. For each participant, spherical equivalent value, cylindrical value, and pupil size were measured in the right eye using the Spot Vision Screener and Grand Seiko autorefractor devices by two different orthoptists under two conditions: monocular and binocular (three consecutive refraction measurements). Repeatability-reproducibility of values measured using both devices were evaluated using intra-class correlation coefficients (ICCs). The mean spherical equivalent value measured using the Spot Vision Screener was -2.79D in the monocular condition and -2.69D in binocular condition, which showed a small significant difference to those measured using the Grand Seiko autorefractor (-2.98D and -2.93D, respectively). The mean cylindrical value measured using the Spot Vision Screener was -0.59D in the monocular condition and -0.52D in the binocular condition, which showed a small significant difference compared with those measured using the Grand Seiko autorefractor in the binocular condition (-0.70D and -0.75D, respectively). Correlation coefficients of the spherical equivalent values, cylindrical values, and pupil sizes measured using both devices were R=0.959 (P<0.001), R=0.243 (P=0.260) and R=0.917 (P<0.001), respectively, in the monocular condition and R=0.962 (P<0.001), R=0.444 (P=0.040), and R=0.832 (P<0.001), respectively, in the binocular condition. ICC values of spherical equivalent value in intra-rater or inter-rater were more than 0.99 in both devices and conditions. ICC values of cylindrical values under the binocular condition in the Spot Vision Screener were 0.636 in intra-rater and 0.574 in inter-rater, which were lower than those of the Grand Seiko autorefractor (0.874 and 0.839, respectively). ICC values of pupil sizes under the binocular condition in the Spot Vision Screener were 0.871 in intra-rater and 0.760 in inter-rater, which were lower than those of the Grand Seiko autorefractor (0.967 and 0.943, respectively). The refractive value and pupil size obtained using the Spot Vision Screener showed high repeatability and reproducibility and were similar to the values obtained using the Grand Seiko autorefractor. Thus, the Spot Vision Screener, an automated vision screener, is a reliable portable refractor and pupillometry device for measuring refractive errors in clinical settings.