Here's a bit more about the effective hypnotic treatment:
After being comfortably seated and asked to close their eyes, subjects were orally administered a 5-min hypnotic induction procedure... Following the induction procedure, and without a break in continuity, subjects were administered a suggestion for wart elimination that was 2 min in duration. The suggestion asked subjects to attend to the sensations in their target hand and informed them repeatedly that the skin around their warts was beginning to tingle and grow warm. The suggestion also informed subjects that their warts would shrink and fall off and asked them to vividly imagine their warts shrinking in size and dissolving away.
The placebo group, which I enjoyed reading about very much (particularly the bit about protective goggles), received a "cold laser treatment." The "laser" was a "metal devise with numerous dials and buttons and an opening in which subjects placed their target hand. When the 'laser' was switched on, it made a whirring sound, and a sweeping pink light could be seen in the opening. Subjects donned 'protective goggles' and placed their hand in the opening for the first of two 4-min 'laser doses.' They were told that they might experience some tingling, prickling, and warmth in their hand during the treatment but not to be alarmed at these sensations."
A third group, the control, received no treatment. At the end of the study, the subjects' remaining warts were tallied, and the researches discovered that hypnotised patients had a 41.48% reduction, "laser" patients a 22.25% reduction, and control patients a 6.39% reduction.
All subjects, recruited via posters plastered in the vicinity of the Carleton campus, were paid $15 for their participation in the study.