The depression and the AMA.
D000574:American Medical Association / Q000266:history*; D004467:Economics / Q000266:history; D005380:Financing, Government / Q000266:history; D005102:Health Expenditures / Q000266:history; D049673:History, 20th Century; D006761:Hospitals / Q000600:supply & distribution; D010820:Physicians; D014481:United States