[troutman]

http://www.skepdic.com/hypnosis.html

Hypnotherapists. While it is true that some hypnotherapists can help some people lose weight, quit smoking, or overcome their fear of flying, it is also true that cognitive-behavioral therapy (CBT) can do the same without any mumbo-jumbo about trance states or brain waves. There have been many scientific studies on the effectiveness of CBT. For example, one systematic study found that CBT improves weight loss in people who are overweight or obese. Another systematic study found that CBT appears to be an effective and acceptable treatment for adult out-patients with chronic fatigue syndrome. Finding high quality scientific evidence for hypnotherapy, however, poses a major problem. As R. Barker Bausell says: hypnosis and the placebo effect are "so heavily reliant upon the effects of suggestion and belief that it would be hard to imagine how a credible placebo control could ever be devised for a hypnotism study" (2007: 268). Even if you could devise a hypnosis study that isolated the role of suggestion and belief, how would you do "fake" hypnosis?

Hypnotherapy is said to effective for such things as helping people lose weight, quit smoking, or overcome a phobia. Most of the evidence for the effectiveness of hypnotherapy is anecdotal, despite the claims of such groups as the American Society of Clinical Hypnosis (ASCH). Not surprisingly, all the anecdotes are positive! Nobody collects examples of failures or tells the world about their "incomplete successes." If one compares the characteristics of the placebo effect and those of hypnotherapy it is hard to distinguish the difference between these two ducks. Both work because participants believe they work and they occur in a clinical setting where the client is highly motivated for the therapy to work and the provider has all the accoutrements of the healing arts. Suggestion is the heart and soul of both.