The purpose of this study was to observe the natural history of untreated syphilis. Although the African-American men who participated in the study were told that they were receiving free health care from the federal government of the United States, they were not.
The Public Health Service started the study in 1932 in collaboration with Tuskegee University (then the Tuskegee Institute), a historically black college in Alabama. In the study, investigators enrolled a total of 600 impoverished African-American sharecroppers from Macon County, Alabama. Of these men, 399 had latent syphilis, with a control group of 201 men who were not infected. As an incentive for participation in the study, the men were promised free medical care, but were deceived by the PHS, who never informed subjects of their diagnosis and disguised placebos, ineffective methods, and diagnostic procedures as treatment.