Here's how it works: imagine an insurer who offered policies to anyone, with the annual premium set to cover the average person's health care expenses, plus the administrative costs of running the insurance company. Who would sign up? The answer, unfortunately, is that the insurer's customers wouldn't be a representative sample of the population. Healthy people, with little reason to expect high medical bills, would probably shun policies priced to reflect the average person's health costs. On the other hand, unhealthy people would find the policies very attractive.
You can see where this is going. The insurance company would quickly find that because its clientele was tilted toward those with high medical costs, its actual costs per customer were much higher than those of the average member of the population. So it would have to raise premiums to cover those higher costs. However, this would disproportionately drive off its healthier customers, leaving it with an even less healthy customer base, requiring a further rise in premiums, and so on.
Saturday, March 04, 2006
Health Care
Krugman and Wells have a good NYRB on health care on what to do about it. It's long so there isn't that much point in excerpting much overall, but I thought this was a nice clear explanation of the problem of adverse selection in insurance markets: