Bell Curve in Medical Care

...the medical profession suffers from a dearth of useful data on outcomes. (I would say the same thing even more strongly about the education profession.)

First, establish the principle that data should be gathered, disclosed, and analyzed.

All activities [including data-gathering] should be subordinated to explicit, meaningful health outcomes. These should be broad. They could include reduced infant mortality; greater welfare-adjusted longevity etc. Government could set these targets and help finance their achievement, but should not prejudge how best to reach them. The private sector would gather data and regulate, only insofar as necessary to achieve the targeted outcomes efficiently. Mutatis mutandis for education. My site explains how this could be done in a way that allows market forces to allocate resources.

Generally the empirical evidence opposes Arnold's claim. It is that the goal of much regulation is to protect people from their own lack of knowledge.

What regulation concerning medical care protects the mediocre from the good?

That medical care outcomes should follow a bell curve, instead of a shark fin is not surprising. I suspect this is the case in the quality/value for many goods and services. If there were no differences amoung center qualities, there could certainly be a bell curve just due to random variations. People leave the poorer centers, some centers innovate and hire better people and become better, and hopefully the bell curve peak moves towards better outcomes.

One thought that occurred to me was that the fee for services model (or the incentivized salary approach of HMO's) in fact shields physicians from precisely this information.

Regulation does not protect the mediocre; inability to formally restrain mediocre practice protects them. Government, the AMA, and State licensing Boards protect the mediocre. A ruthless application of Law could vastly improve health care: All Doctors and Hospitals to be examined every decade, with 10% of both Doctors and Hospitals with the poorest records to be decertifed from the practice of medicine. lgl

How does this Bell Curve demonstrate that there is any difference in quality between doctors or hospitals? Isn't a bell curve exactly the distribution you would expect from a bunch of independent samples? (hospital = sample, single patient event = one sampling).

I saw this story earlier and was baffled as to why the conclusion drawn was that centers are different. If I flip a coin 10 times, and do that 100 times, and I get a bell-shaped distribution of number of heads, do I conclude that the different sets had different head-generating ability?

Kudos to Patri!

Indeed this is the case. This assumes that observations of different hospitals is independent though.

I wouldn't say the protection of mediocrity is the goal of regulation as much as an unintended consequence. Except maybe in the cable TV business.

I've seen a lot of discussion about private rankings of physicians, based on customer polls or something like this. But this survey, and the comment about multivariate analysis demonstrates the diffence in public knowledge is too great for this to work.

I must say that it also mystifies me why Gatawande expected to find anything other than a normal distribution of this data, and I notice that he doesn't actually provide a citation for anyone having ever said that they thought medical outcomes would have the weird right-skewed distribution he describes. In fact, thinking about it, every medical statistics textbook I've ever seen (all two of them) operates off an implicit assumption of normality. I'm calling "shenanigans" here.

(I also disagree with Arnold's assertion that "Such a Darwinian process can be taken for granted in most markets". I can't think of a single market in which I couldn't name at least one utterly mediocre or substandard player. It's also not the case that it is typically the lowest-quality providers which go under in markets; it's often high-quality providers who are driven out because of poor cost control, marketing or financing)