At yesterday’s Cato policy forum on pay-for-performance (P4P) in Medicare, I argued the Medicare bureaucracy should stay out of P4P largely because Medicare would ruin the idea. A Medicare-administered P4P program would be less flexible than private efforts, more likely to harm patients, and the very providers that P4P aims to discipline would have way too much say in a Medicare P4P program. I recommended confining P4P to private Medicare Advantage health plans. Read my full argument here.

Harvard’s David Cutler argued that Medicare should get involved in P4P because private insurers didn’t have the purchasing power to really force providers to change. At the time, I was unaware of this study by Meredith Rosenthal and her colleagues in this week’s New England Journal of Medicine. They report:

More than half the HMOs, representing more than 80%of persons enrolled, use pay for performance in their providercontracts. Of the 126 health plans with pay-for-performanceprograms, nearly 90% had programs for physicians and 38% hadprograms for hospitals.

That probably doesn’t match Medicare’s purchasing power. But it does suggest that P4P can gain a toehold through the private sector.