Bland & Altman and Paired t-Test Difference Plots

The Bland & Altman method comparison compares two methods of measurement or two paired variables, and provides a plot of difference vs. mean, in which the standard deviation of differences between measurements made by the two methods provides an index of the comparability of the methods.

In Aabel, the Bland & Altman method for comparing two methods of measurement or two paired variables provides:

• A plot of differences
• A plot of differences as a % of averages
• A plot of ratios

• Aabel has the option of showing:
  • The ±1.96 standard deviation, which is commonly used in a typical Bland & Altman plot
  • A paired t-test difference plot with the 95% CI of mean difference above and below the mean line
  • A paired t-test difference plot with the 99% CI of mean difference above and below the mean line