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10870 Studies found for: Placebo AND once
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Map Legend
Region Name Number of Studies
World [map] 10,870
North America 5,834
United States 5,365 [studies]
Alabama 1,187 [studies]
Alaska 54 [studies]
Arizona 1,342 [studies]
Arkansas 663 [studies]
California 2,905 [studies]
Colorado 1,209 [studies]
Connecticut 854 [studies]
Delaware 124 [studies]
District of Columbia 389 [studies]
Florida 2,493 [studies]
Georgia 1,559 [studies]
Hawaii 191 [studies]
Idaho 425 [studies]
Illinois 1,613 [studies]
Indiana 1,114 [studies]
Iowa 443 [studies]
Kansas 886 [studies]
Kentucky 869 [studies]
Louisiana 963 [studies]
Maine 231 [studies]
Maryland 1,347 [studies]
Massachusetts 1,356 [studies]
Michigan 1,296 [studies]
Minnesota 886 [studies]
Mississippi 402 [studies]
Missouri 1,362 [studies]
Montana 289 [studies]
Nebraska 686 [studies]
Nevada 663 [studies]
New Hampshire 216 [studies]
New Jersey 1,201 [studies]
New Mexico 481 [studies]
New York 2,132 [studies]
North Carolina 1,874 [studies]
North Dakota 238 [studies]
Ohio 1,907 [studies]
Oklahoma 910 [studies]
Oregon 923 [studies]
Pennsylvania 1,841 [studies]
Rhode Island 431 [studies]
South Carolina 1,268 [studies]
South Dakota 199 [studies]
Tennessee 1,275 [studies]
Texas 2,594 [studies]
Utah 867 [studies]
Vermont 224 [studies]
Virginia 1,293 [studies]
Washington 1,231 [studies]
West Virginia 163 [studies]
Wisconsin 702 [studies]
Wyoming 19 [studies]

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