The effect of daily prefrontal repetitive transcranial magnetic stimulation over several weeks on resting motor threshold

Daily left prefrontal rTMS over several weeks as delivered in this trial does not cause systematic changes in rMT. Although most subjects had less than 10% variance in rMT over time, five subjects had changes of approximately 20% from baseline, raising dosing and safety issues if undetected. We recommend that clinical trials of rTMS have periodic retesting of rMT, especially if the dose is at or near the edge of the TMS safety tables.