Phenomenon that occurs when people are given a sugar pill and told that it is a drug that will help their disease. An astounding 16-33% in ANY study will say that it works. They represent people who would have gotten better anyway, who are suggestable, or well, whatever. The flip side is that they also report side effects. In any study of a drug's effectiveness, the rate of success and side effects are statistically compared to see how much good/harm the drug is doing compared to placebo.