Figure 3
From: Photorefraction estimates of refractive power varies with the ethnic origin of human eyes
Myopia of Indian eyes estimated using PowerRef 3™ plotted against those obtained using retinoscopy.
(Panel A) shows data obtained using the instrument's default calibration factor while (panels B and C) show data obtained by rescaling the PowerRef 3™ values using the Indian eye's population-average and individual's own calibration factor, respectively. The diagonal black line in each panel indicates equal refractive error estimates recorded by both instruments. The solid red line in each panel shows the best-fit orthogonal linear regression line plotted to the data while the dashed curves around the best-fit line show the ±95% confidence interval of the linear regression fit. (Panels D–F) show Bland-Altman type plots of the difference in refractive error estimates obtained from PowerRef 3™ and retinoscopy plotted as a function of the mean refractive error estimates obtained from the two techniques. (Panels D) shows data obtained using the instrument's default calibration factor while (panels E and F) show data obtained by rescaling the PowerRef 3™ values using the Indian eye's population-average and individual's own calibration factor, respectively. The solid red line in (panel D) show the best-fit orthogonal linear regression line plotted to the data. The solid and dashed red lines in (panels E and F) show the mean difference and ±95% limits of agreement, respectively.
