A study reviewing the CMS cardiac care P4P program published in today’s issue of JAMA shows no significant improvement in care associated with P4P "carrots." See Washington Post story here, WSJ story here (subscription may be required) and Duke press release here.
Possible explanations: observed behavior improves regardless of incentive; cardiac care is improving generally; the carrot wasn’t big enough. (Tip of the hat carrot to Kevin MD.)
I don’t see this as the death knell for P4P, but rather as a call for further study and tweaking. There are many possible paths to improved performance in health care. (See earlier HealthBlawg posts on P4P, including this one.)