title: The managed care era: untangling preauthorization requirements in the ED.
mesh_terms: D003362:Cost-Benefit Analysis; D004636:Emergency Service, Hospital / Q000191:economics* / Q000706:statistics & numerical data; D006279:Health Maintenance Organizations / Q000458:organization & administration*; D006297:Health Services Accessibility; D007345:Insurance Claim Review; D008484:Medicaid; D017008:Negotiating; D014481:United States