For the applications demonstrated here, PCA and the correction
technique were applied separately to each plane of the joint angles
and moments. PCA and the correction procedure were performed
in MATLAB (The Mathworks Inc., Natick, MA). Here, the mean PC
scores from each centre were used to calculate the correction;
however, if the dataset contains outliers that may influence the
mean, it may be advisable to use a trimmed mean or other variant
when calculating zAi and zBi