National Research Act In 1974, http://www.cdc.gov/tuskegee/after.htm In 1974, brought sweeping improvements In 1974, "How Tuskegee Changed Research Practices" brought sweeping improvements In 1974, http://www.cdc.gov/tuskegee/after.htm In 1974, 1974 National Research Act 1974 National Research Act 1974 National Research Act