Pay for performance is one of those slogans that seems to upset no one. But as with so many things in health care, it’s much more complicated than it appears at first glance. It's also the topic of this week's Healthcare Triage.

(Intro)   To most people it's a no brainer that we should pay for quality and not quantity. We all know that paying doctors based on the amount of care they provide, as we do with traditional fee for service setup, creates incentive for them to give more care. It leads to increased healthcare spending.    Changing the payment structure to pay doctors for achieving goals instead should reduce wasteful spending. So it's no surprise that pay for performance has been an important part of recent reform efforts. But in reality, we're seeing disappointingly mixed results.    Sometimes it's because doctors don't change the way they practice medicine. Sometimes its because even when they do, outcomes don't really improve.   The idea behind pay for performance is simple: we'll give providers more money for achieving a goal. That goal can be defined in various ways, but at its heart we want to see the system hit some target. This could be a certain number of patients receiving preventative care, a certain percentage of people whose chronic disease is being properly managed or even a certain number of people avoiding a bad outcome. Providers who reach these targets earn more money.   The problem, one we've discussed before, is that changing physician behavior is hard. Sure, it's possible to find a study in the medical literature that shows that pay for performance worked in some small way here or there. For instance, a study published last fall found that paying doctors two hundred dollars more per patient for hitting certain performance criteria resulted in improvements in care. It found that the rate of recommendations for aspirin or for prescriptions for medications to prevent clotting for people who needed it increased six percent in clinics without pay for performance but twelve percent in clinics with it.   Good blood pressure control increased 4.3 percent in clinics without pay for performances, but 9.7 percent in clinics with it. But even in the pay for performance clinics, thirty-five percent of patients still didn't have the appropriate anti-clotting advice or prescriptions and thirty-eight percent of patients didn't have proper hypertensive care. And that's success!   It's also worth noting that the study was only for one year, and many improvements and actual outcomes would need to be sustained for much longer to matter. It's not clear whether that will happen.   A study published in the journal Health Affairs examined the effects of a government partnership with Premier Inc., a national hospital system, and found that while the improvements seen in 260 hospitals in a pay-for-performance project outpaced those of 780 not in the project, five years later all of those differences were gone.   The studies showing failure are also compelling. A study in The New England Journal of Medicine looked at 30-day mortality in the hospitals in the Premier pay-for-performance program compared with 3,363 hospitals that weren't part of the pay-for-performance intervention. We're talking about a study of millions of patients taking place over a six-year period in twelve states. Researchers found that 30-day mortality, or the rate at which people died within a month after receiving certain procedures or care, was similar at the start of the study between the two groups and that the decline in mortality over the next six years was also similar. Moreover, they found that even among the conditions that were explicitly linked to incentives, like heart attacks and coronary artery bypass grafts, pay for performance resulted in no improvements compared with conditions without financial incentives.   In Britain, a program was begun over a decade ago that would pay general practitioners up to twenty-five percent of their income in bonuses if they met certain benchmarks in the management of chronic diseases. The program made no difference at all in physician practice or patient outcomes, and this was with a much larger financial incentive than most programs in the United States might offer.   Even refusing to pay for bad outcomes doesn't appear to work as well as you might think. A 2012 study published again in The New England Journal of Medicine looked at how the 2008 Medicare policy to refuse to pay for certain hospital-acquired conditions affected the rates of such infections. Those who devised the policy imagined that it would lead hospitals to improve their care of patients to prevent these infections. That didn't happen. The policy had almost no measurable effect.    There have even been two systematic reviews in this area. The first of them suggested that there's some evidence that pay for performance could change physician's behavior. It acknowledged, though, that the studies were limited and how they could be generalized and might not be able to be replicated. It also noted that there was no evidence that pay for performance improved patient outcomes, which is what we really care about.   The second review found that with respect to primary care physicians, there was no evidence that pay for performance could even change physician behavior, let alone patient outcomes.   One of the reasons that paying for quality is hard is that we don't even really know how to define "quality." What is it really? Far too often we approach quality like the drunkard search - looking where it's easy rather than where it's necessary. But it's very hard to measure the things we really care about, like quality of life and improvements in functioning.    In fact, the way we keep setting up pay for performance demands easy-to-obtain metrics, otherwise the cost of data gathering could overwhelm any incentives. Unfortunately, as a recent New York Times article described, this has drawbacks.    The National Quality Forum, described in the article as an influential, non-profit, non-partisan organization that endorses healthcare standards, reported that the metrics chosen by Medicare for their programs included measurements that were outside the control of a provider; in other words, factors like income, housing, and education can affect the quality metrics more than what doctors and hospitals might do.   This means that hospitals in resource-starved setting caring for the poor might be penalized because what we measure is out of their hands. A panel, commissioned by the current United States administration recommended that the Department of Health and Human Services change the program to acknowledge this flaw. To date, it hasn't agreed to do so.   Some fear that pay for performance could even backfire. Studies in other fields show offering extrinsic rewards, like financial incentives, can undermine intrinsic motivations, like a desire to help people. Many physicians choose to do what they do because of the latter. It would be a tragedy if pay for performance wound up doing more harm than good.