How should groups be chosen for systematic x-raying for case-finding, and how often should case-finding examinations be repeated?
D000293:Adolescent; D000328:Adult; D000368:Aged; D003604:Czechoslovakia; D005260:Female; D006801:Humans; D008297:Male; D008400:Mass Chest X-Ray; D008875:Middle Aged; D014397:Tuberculosis, Pulmonary / Q000000981:diagnostic imaging* / Q000517:prevention & control