Periodically you will hear teachers complain about VAM and similar test-and-punish versions of evaluation by saying, "Imagine how ridiculous it would be if they did this to doctors. That would be so stupid they'd never even consider it." These are teachers who don't have friends and family in the medical field. Because (bad news alert) the Powers That Be have totally been doing the same crap to doctors that they've been doing to us.
The idea has been kicking around since the eighties, but one backbone of the Affordable Care Act (and many other proposed health care reforms) is an informed customer base that is able to choose physicians based on solid ratings. This would also, not coincidentally, allow the behemoths who manage the highly-profitable non-profit health care providers to have a data-based means of deciding which doctors to keep and which to boot.
Of course, the key here is coming up with a metric-- or metrics-- to determine which doctors are effective and which are not effective. And that turns out to be hard.
You know the arguments-- you've already made them. Can we judge a doctor on how effective he is with a patient who is high risk and who insists on engaging in risky behavior? Is it fair to give a lower score to a physician who works with more difficult patients-- and will she keep taking more difficult patients if they will make her rating look bad?
Well, we may not know how to measure physician effectiveness, but we know what happens when we try to measure effectiveness with a crappy instrument.
The New York Times ran a piece referring us to some of the research done on the effects of mandatory surgeon report cards that are based on patient outcomes. You will be Not Shocked to discover that it makes things worse. The top surgeons focus on low-risk patients, and innovation and risk-taking are squelched. Top surgeons who took the tough cases, the patients who had no other hope, sometimes found themselves with low ratings and a loss of operating privileges.
The whole story is completely recognizable to those of us in the education world, the major difference being that nobody-- yet-- is forcing doctors to treat patients that will hurt their numbers in order to force those physicians out so that they can be replaced by low-cost under-trained temps. But the principle is the same-- when you set up a system that punishes professionals for trying to help the most needy, you get crappy results.