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8136 Studies found for: sleep AND sleep quality

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Map Legend
Region Name Number of Studies
World 8,136
Africa [map] 79
Central America [map] 27
East Asia [map] 947
Japan 96 [studies]
Europe [map] 2,351
Middle East [map] 521
North America 3,419
Canada [map] 499 [studies]
Mexico 42 [studies]
United States [map] 2,995 [studies]
North Asia [map] 66
Pacifica [map] 100
South America [map] 250
South Asia [map] 73
Southeast Asia [map] 105

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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.