Fig. 1

The left plots show Bland–Altman plots for A1- front flat keratometry (D), B1- front steep K (D), C1- back flat K (D) and D1- back steep K(D) comparing Sirius (Costruzione Strumenti Oftalmici, Florence, Italy) vs. Scansys (MediWorks, Shanghai, China). The mean difference, 95% limits of agreement and regression line are shown by blue solid line, red and pink dash-dotted lines, respectively. The right Scatter plots compare mean values of A2- front flat keratometry (D), B2- front steep K (D), C2- back flat K (D) and D2- back steep K (D) measured with Sirius (Costruzione Strumenti Oftalmici, Florence, Italy) and Scansys (MediWorks, Shanghai, China). The blue dash-dotted lines show the regression lines. K, keratometry