Evaluating distant healing: a research review.

The term "distant healing" describes any purely mental effort undertaken by one person with the intention to improve physical or emotional well-being in another. Various forms of distant healing including prayer and "psychic healing" are widely used throughout the United States and other parts of the world. There currently exist numerous, well-controlled experimental trials demonstrating distant mental effects on humans, animals, and other biological systems. At this time, however, insufficient formal research trials have been completed to definitively determine whether such activities do in fact have a clinical impact independent of psychological effects. The key in studying the concept of distant healing is separating the putative distant effect from changes that may be due to causes such as hope, expectation, relaxation, or other participation activities. This review discusses some of the most compelling evidence for a genuine distant healing effect and identifies correctable methodological issues that frequently confound research in this area.