A functional diagram showing how alternative medicine works through three separate pathways. 
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"The three pathways by which alternative treatments "work":
a) Regression to the mean — an individual who would have gotten better anyway is given a treatment. When the individual gets better, the "alternative therapy" is given credit for spontaneous improvement.
b) Placebo or false treatment — an individual who receives an "alternative therapy" (here illustrated as a pill) is convinced that the treatment will help. This conviction in turn makes the individual more likely to get better.
c) Decreased side-effects — an individual who has a disease and is medicated experiences side effects, such as nausea. When given an "alternative therapy" this therapy has an effect — namely to decrease the effect of the functional treatment. The side effects diminish, making the patient less likely to have nausea, but also less likely to recover.
How treatments work is studied by researchers such as epidemiologists, clinical statisticians and pharmacists in clinical trials. Clinical trials are designed to avoid these pitfalls. Cases a &amp; c are avoided by using randomized controlled trials, with or without double blinding.  
Alternative medicine often makes it deliberately hard or even impossible to tease use such research methodology."
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CFCF