Problem: A study involved a group of children diagnosed with mental retardation, who lived at a state hospital for children with mental retardation. The children were deliberately infected with a contagious disease. The study's purpose was to study the history of the disease when left untreated and later to assess the effects of a new medication as a treatment. Parents were encouraged to enroll their children in the study in exchange for admission of their child to the state hospital (which was deliberately short of space).