Bland-Altman Plot

Creates a Bland-Altman plot (also known as Tukey mean-difference plot) used to analyze the agreement of two different measurement methods.

The plot shows the relationship between the mean of two measurements (x-axis) and the difference of the two measurements (y-axis). It can be used to assess whether the two methods agree sufficiently well over the range of measurements and to identify possible systematic deviations or outliers.

The bias (mean of the differences) and the limits of agreement (bias ± 1.96 standard deviations of the differences) are shown as horizontal lines. If the differences are approximately normally distributed, about 95% of the points are expected to lie within these limits.

For details, see: Bland JM, Altman DG (1986) Statistical methods for assessing agreement between two methods of clinical measurement . Lancet 1(8476):307-310. https://doi.org/10.1016/S0140-6736(86)90837-8 .

Input ports

1. Type: Table
   Measurement data
   Data table containing the two measurements.

Output ports

1. Type: Image
   Bland-Altman Plot
   The Bland-Altman Plot.
2. Type: Table
   Measurements
   The two selected measurements together with the calculated mean (x in the plot) and difference (y in the plot).
3. Type: Table
   Bias and limits of agreement
   The bias (mean of the difference) and the limits of agreement (95% of the points are within the limits of agreement).