Assessing the quality of the electrical contact between transcutaneous stimulation electrodes and a patient’s skin. The system comprises an array of least three electrodes A, B, C, where the electrodes may be paired to form a conductive pathway and where two electrode pairings AB, BC of the array share a common electrode B. Stimulation pulses are passed between different electrode pairings and at least one voltage, Vab, Vac, Vbc, is measured across each in response to a constant current pulse. Faulty electrodes may be identified by comparing measured voltages with reference values. A plurality of voltages may be measured at time-points during the stimulation pulse. Voltages may be recorded across each electrode pairing and the voltage drop of each individual electrode may be calculated from them. The system may alert a user to a faulty electrode contact and may form part of a garment, belt, module or applicator.
