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3410 Studies found for: subjects AND Double-blind AND City

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Map Legend
Region Name Number of Studies
World 3,410
Africa [map] 374
Central America [map] 349
East Asia [map] 853
Japan 392 [studies]
Europe [map] 1,553
Middle East [map] 529
North America 3,117
Canada [map] 1,201 [studies]
Mexico 552 [studies]
United States [map] 3,051 [studies]
North Asia [map] 804
Pacifica [map] 726
South America [map] 681
South Asia [map] 247
Southeast Asia [map] 385

Click on a [map] link to show a map of that region.

Click on a [studies] link to search within your current results for studies in that region. Use the back button to return to this list and try another region.

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.