title: HCFA clarifies use of modifiers for outpatient hospital services.
mesh_terms: D000043:Abstracting and Indexing / Q000592:standards; D000368:Aged; D014487:Centers for Medicare and Medicaid Services, U.S.; D006801:Humans; D007344:Insurance Claim Reporting / Q000145:classification*; D006278:Medicare; D010044:Outpatient Clinics, Hospital / Q000191:economics*; D011445:Prospective Payment System; D012046:Rehabilitation / Q000145:classification; D014481:United States