Scatter and Bland-Altman plots of the pairwise comparisons of carotid IMT. Measurements of carotid IMT - average of left and right side measurements on the absolute scale (mm). Comparisons across visits (A/B), sonographers (X/Y) and readers (x/y). Replicate measurements are randomly permuted within each combination of these three factors. Points and lines in red are for persons with T2D, in blue for persons without T2D. The panels above the diagonal are Bland-Altman plots of the differences of the pairwise comparisons of carotid IMT. Plots below the diagonal are just the corresponding scatter plots. Limits of agreement are given in brackets (), red for T2D and blue for persons without T2D. Visits: A and B, sonographers: X and Y, readers: X and y. Symbols in plot: S = sonographer variability, R = reader variability, D = day-to-day variability, S + R = combined sonographer and reader variability, S + D = combined sonographer and day-to-day variability, R + D = combined reader and day-to-day variability, S + R + D = combined sonographer, reader and day-to-day variability.