Correcting MRI-specific biases introduced when Bland-Altman plots are used to compare the performance of reconstruction algorithms

The Bland-Altman plot is a commonly-used graphical method to compare two measurement techniques and look for systematic biases or outliers. We have identified that the Bland-Altman approach of plotting the differences between the two techniques against their average will introduce false biases in an MRI context. These biases are introduced by the magnitude operation necessary to display or analyze MRI images. We demonstrate a modified Bland-Altman approach that corrects these biases.