To perform Bland Altman analysis in Excel, calculate the average and difference for each pair of measurements, find the bias and limits of agreement using bias ± 1.96 × standard deviation of differences, and create an XY scatter plot with horizontal lines for bias and agreement limits.
A Bland Altman analysis Excel workflow helps when you have paired measurements from two methods and need to calculate agreement values, create a plot, and make a practical decision. This guide shows how to organize paired data, calculate bias and limits of agreement, create the Bland–Altman plot, and judge whether the differences are acceptable for the intended use. See also the broader Bland Altman analysis topic for additional context.
A Bland–Altman analysis measures agreement between two methods by plotting the difference between paired measurements against their average. It is appropriate when both methods measure the same quantity and the goal is to understand how closely individual results agree, not simply whether the methods change together.
In Excel, the workflow is based on calculating each pair’s average and signed difference, finding the mean difference (bias), calculating limits of agreement as bias ± 1.96 × standard deviation of differences, and displaying these values on an XY scatter plot.