Medicare in Maryland hospitals. July 1966 and January 1967.
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D002675:Child, Preschool; D006761:Hospitals; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008396:Maryland; D006278:Medicare; D008875:Middle Aged