Letters Section Editor: Robert M. Golub,
MD, Senior Editor.
In Reply: As noted by Dr Milic and colleagues,
we used the incorrect formula taken from the article by Moss.1 We
have recalculated our results using the correct formula for linear corrected
QTc intervals. When the Framingham Linear Correction is properly used, the
differences in the postdosing QTc interval values between the DSEC and placebo
groups are of the same magnitude and direction as those derived from the Bazett
formula (20.3-millisecond increase with DSEC; 400.5 milliseconds [SD, 10.7]
vs 380.2 milliseconds [SD, 15.3]; P<.001).
White CM, McBride BF. Electrocardiographic Effects of a Dietary Supplement Containing Ephedra
and Caffeine—Reply. JAMA. 2005;294(12):1487-1488. doi:10.1001/jama.294.12.1487-b