What Do We Mean By "The Uninsured?"

What do we mean by the “uninsured?”
We recently overhauled our entire health care system, in large part driven by the concern that there are 47 million uninsured Americans and the suspicion that this number has been growing ever larger. So, this raises the question, actually how many people are uninsured?
If we look over time, here we’re looking at the United States from 1987 to 2007, the percentage of the population that is uninsured has remained remarkably stable. It’s fluctuated from a low of about 13 percent to a high of 16 percent, and this is during periods of recession and expansion. What we’ve been told is that 15 percent of the population is uninsured. This is the 47 million figure. The way we know this number is that the Census Bureau calls up households at random and asks, “Are you insured, or uninsured? And if you’re insured, have you ever been uninsured at any point in the past year?” If the answer is yes, you’re marked down as being uninsured.
Well, the fact is, subsequent studies indicate that not all of these people who say they’re uninsured are in fact uninsured. There’s a small percentage of people who claim to be uninsured but actually aren’t. Studies indicate that they misunderstand the question to mean, “Do you have private insurance”—as opposed to do you have some form of Medicare or Medicaid?
There’s another small percentage of people who are Medicaid eligible, that is, although they aren’t signed up for Medicaid, they’re eligible for it. So that if they ever went in to a hospital for some kind of procedure, the first thing that happens is the registration folks check and see that this person is Medicaid eligible. The person is immediately automatically enrolled to Medicaid, and Medicaid covers all of the expenses. So these people can legitimately say, yes they are uninsured. However, de facto, they have insurance if they ever need it.
There’s another group of people who you would say, yes, I was uninsured at some point in the past year, and they’re marked down as being uninsured, when in fact these people are uninsured for less than four months. So that’s certainly not who we would call the chronically uninsured.
There’s another group of people who are 18–34 and childless. Of all the people who would voluntarily choose not to buy insurance but to buy something else instead, that is the group of people we would expect to choose not to buy insurance. So if we take out these slices of population, what we’re left with is about 4 percent of the population. And if you want to count the 18–34 and childless, maybe we’ve got 6 percent of the population, who are truly uninsured and uninsured chronically. Those are the people that we should be concerned about.
Now, this does not mean that we should ignore these people, but on the other hand, it calls into question whether it was wise to upend an entire industry to help what turns out to be not 47 million people but 12 million.