The CMS policy of withholding additional Medicare payment for mediastinitis was not associated with a reduction in actual infection rates during the first 2 years after policy implementation. Similar findings were associated with catheter-associated urinary tract infections (CAUTIs), which actually continued to rise after Medicare instituted payment reduction policies. Notwithstanding the lack of reduction or production in increased rates of healthcare associated infections, claims-based evidence showed changes in coding for infections but not reduction in infections.