Figure 3From: Validation, reproducibility and safety of trans dermal electrical stimulation in chronic pain patients and healthy volunteers Average time course (0-75 min) of NRS (left panel) and VAS (right panel) pain scores at each visit. The electrical stimulation was maintained for 155 minutes in HVs; and for 85 minutes in patients. Thick line, healthy volunteers; dotted lines, patients. Circles, Visit1; Crosses, Visit2.Back to article page