The subset of participants reporting MDS use totaled 149. Principal axis factoring was carried out, followed by varimax rotation with Kaiser normalization. Rotations converged in six iterations. The KMO measure of sampling adequacy and Bartlette's tests of sphericity provided support for the validity of factor analysis on the dataset. Varimax rotation facilitated interpretability. Initial runs showed, on the basis of a scree plot and eigenvalues, support for five factors, which explained 48% of the total variation.