Carriers paid according to Reasonable and Customary fees.  Then they negotiated discounts and called them Preferred Provider Organizations.  Now they are taking advantage of a new trend toward value based reimbursement.  UnitedHealth, the largest medical insurance carrier in the country, has announced that they will increase value based payments to doctors and hospitals by 20% – which translates to more than $43 billion.  Value based payments include pay for performance, patient centered medical homes and Accountable Care Organizations, all of which have been gaining favor on their own – now UnitedHealth can use all of them.  The changes keep on coming…along with provider pressure.