title: Co-operative international study on the demographic and geographic distribution of low, medium and high grade tuberculin sensitivity.
mesh_terms: D000995:Antitubercular Agents / Q000627:therapeutic use; D001500:BCG Vaccine; D005060:Europe; D006801:Humans; D006968:Hypersensitivity, Delayed; D007391:International Cooperation; D008954:Models, Biological; D014374:Tuberculin Test; D014376:Tuberculosis / Q000453:epidemiology*; D014837:Voluntary Health Agencies
chemical_list: D000995:Antitubercular Agents; D001500:BCG Vaccine