It's everywhere. But measuring effectivenes of P4P is challenging.
Vesely
Rebecca
R
D001291:Attitude of Health Personnel; D004059:Diffusion of Innovation; D019538:Health Care Surveys; D006761:Hospitals / Q000706:statistics & numerical data; D006801:Humans; D010820:Physicians / Q000706:statistics & numerical data; D012052:Reimbursement, Incentive; D014481:United States