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176646 Studies found for: Participants

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Click on the map below to show a more detailed map (when available) or search for studies (when map not available).

Map Legend
Region Name Number of Studies
World 176,646
Africa [map] 6,968
Central America [map] 2,181
East Asia [map] 21,322
Japan 4,149 [studies]
Europe [map] 45,076
Middle East [map] 9,083
North America 84,964
Canada [map] 14,100 [studies]
Mexico 2,974 [studies]
United States [map] 76,170 [studies]
North Asia [map] 4,890
Pacifica [map] 6,040
South America [map] 7,290
South Asia [map] 3,533
Southeast Asia [map] 4,650

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.