Interstudy report shows providers give larger discounts to national PPOs.
D014487:Centers for Medicare and Medicaid Services, U.S.; D003625:Data Collection; D005249:Fees and Charges / Q000706:statistics & numerical data; D019458:Insurance Coverage / Q000706:statistics & numerical data; D011243:Preferred Provider Organizations / Q000191:economics / Q000706:statistics & numerical data*; D014481:United States