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13970 Studies found for: subjects AND Double-blind AND Placebo-Controlled

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Map Legend
Region Name Number of Studies
World 13,970
Africa [map] 537
Central America [map] 407
East Asia [map] 2,143
Japan 732 [studies]
Europe [map] 4,598
Middle East [map] 838
North America 7,962
Canada [map] 1,894 [studies]
Mexico 610 [studies]
United States [map] 7,538 [studies]
North Asia [map] 1,115
Pacifica [map] 1,177
South America [map] 910
South Asia [map] 379
Southeast Asia [map] 529

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Studies with no locations are not included in the counts or on the map.

Studies with multiple locations are included in each region containing locations.