Placebo responses concepts

Thus, Lind showed the importance of the comparative trial and Evans and Hoyle showed the importance of the placebo effect in evaluating drug response. Gold et at. then showed the importance of observer bias and introduced the concept of the double-blind study in 1937 in a study of treatments for angina patients. They wrote ... 

To test for the hallucinogenic activity of S. divinorum in human beings, we drank the infusion of the leaves and waited for the effects to occur. Within 30 min we began to see visions, which lasted for several hours. This allowed rapid confirmation of the mint s psychotropic activity. But more interesting from a therapeutic standpoint are the other properties attributed to the plant properties that are much more difficult to assess. Are these concepts that are translatable into our western (orthodox) healing theory, or is ska Maria Pastora being used as a magical treatment (for a placebo effect) Extended observations in the field by an acute observer would undoubtedly be more fruitful than immediate attempts to isolate compounds responsible for these purported activities. 

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