QT dispersion validity in view of measurement accuracy

QT dispersion measurements have gained a lot of attention by clinical cardiologists because high QT dispersion is associated with risk of arrhythmia, infarction, cardiomyopathy and other cardiac diseases. To the authors' knowledge there is only one systematic study which investigates the reproducibility of QT dispersion measurements at different body positions with regard to biological stability. However, to the authors' knowledge the technical aspect of uncertainty in determination of T end has so far not been quantitatively examined.