Australia
Austria
Belize
Brazil
Canada
China
Finland
France
Germany
Hungary
India
Indus Valley civilization
Ireland
Japan
Kazakhstan
Netherlands
Poland
Spain
Sweden
United Kingdom (including all New Towns under the New Towns Act of 1946 and successive Acts)
United States
... a person's perception of their illness. People report reduced pain, and increased well being, all because they don't no their treatment does nothing. The placebo effect is ...