Oslo study
The Oslo study (1891–1910) was an observational study of untreated syphilis at Oslo University Hospital, Rikshospitalet in Oslo, Norway. Under the supervision of the department head, Cæsar Boeck, treatment was withheld from approximately 2,000 patients with syphilis between the period of 1891 and 1910. The results of Boeck's patient observations were later documented by his successor Edvin Bruusgaard in the paper "The Fate of Syphilitics who had received no Specific Treatment" (1929).
The results of the study greatly influenced American researchers who conducted the Tuskegee Syphilis Study (1932–1972), in which treatment was withheld from African American men with syphilis.