EFFICACY OF CLINICAL HYPNOSIS: A SUMMARY OF ITS EMPIRICAL EVIDENCE

ypnosis is a field of study with a great deal of theoretical, clinical, and experimental research. However, a good number of studies on the efficacy of applied clinical hypnosis do not meet stringent methodological criteria in several areas of its application. A comprehensive review of the state of the empirical evidence regarding the efficacy of hypnosis was published in a special issue of the International Journal of Clinical and Experimental Hypnosis (2000, Vol. 48, 2). The criteria on which the evaluation of the empirical status of clinical hypnosis was based in all the reviews were those delineated by Chambless and Hollon (1998). These methodological guidelines are among the most rigorous in existence today. Therefore, the fact that a particular study does not comply with all the criteria does not necessarily mean that the treatment under study is ineffective, but rather that both continued research and the improvement of interventions are needed in order to achieve such criteria (Lynn, Kirsch, Barabasz, Cardeña, & Patterson, 2000). More recently, while this paper was still being edited, Wark (2008) published a brief review in which results from the main meta-analyses conducted on the efficacy of clinical hypnosis are summarized. Although it may be slightly optimistic, this summary is, however, useful for guiding those professionals who want to use hypnosis in the treatment of those problems or areas in which a minimum degree of efficacy/efficiency has been shown. The present paper also attempts to meet that goal, as well as to be a more comprehensive and updated review than that of Wark, taking into account a wide range of studies relevant to the establishment of the efficacy of clinical hypnosis