Uncovering Some Really Bad Science
Kevin Drum thinks he has a killer analysis supporting government health care. In a post he titles sarcastically "Best Healthcare In the World, Baby," Drum shares this chart:
The implication is that the US has the worst healthcare system, because, according to this study, the US has the highest rates of "amenable mortality," defined as deaths that are "potentially preventable with timely and effective health care."
I get caught from time to time linking to studies that turn out to have crappy methodology. However, I do try to do a little due diligence each time to at least look at their approach, particularly when the authors are claiming to measure something so non-objective as mortality that was "potentially preventable."
So, when in doubt, let's look at what the author's have to say about their methodology. The press release is here, which gets us nowhere. From there, though, one can link to here and then download the article from Health Affairs via pdf (the site is gated but I found that if you go through the press release site you can get in for free).
The wording of the study and the chart as quoted by Mr. Drum seem to imply that someone has gone through a sampling of medical histories to look at deaths to decide if they were preventable deaths. Some studies like this have been conducted. This is not one of them. The authors do not look at any patient data.
Here is what they actually did: They arbitrarily defined a handful of conditions as "amenable" to care. These are:
Ischemic Heart Disease (IHD)
Other circulatory diseases
Neoplasms (some cancers)
Diabetes
Respiratory diseases
Surgical conditions and medical errors
Infectious Diseases.
Perinatal, congenital, and maternal conditions
Other (very small)
All the study does is show how many people died in each country from this set of diseases and conditions. Period. It doesn't determine if they got care or if they in particular could have been saved, but just that they died of one of the above list of conditions. This study was not an effort to identify people who died when their particular condition should have been preventable or amenable to care; all it measures is the number of people in each country who died from list of conditions. If Joe is talking to me and in the next second flops over instantly dead of a massive heart attack, the author's consider him to have died of a disease amenable to care.
We can learn something by looking at the breakdown of the data. If you can't read the table below, click on it for a larger version
Let's take the data for men. The study makes a big point of saying that France is much better than the US, so we will use those two countries. In 2003, France has an "amenable disease" death rate 56 points lower than the US. But we can see that almost this whole gap, or 42 points of it, comes from heart and circulatory diseases. The incidence of these diseases are highly related to diet and lifestyle. In fact, it is well established that the US has a comparatively high incidence rate of these diseases, much higher than France. This makes it entirely possible that this mortality difference is entirely due to lifestyle differences and disease incidence rates rather than the relative merits of health care systems. In fact, this study is close to meaningless. If they really wanted to make a point about the quality of health care systems, they would compare them on relative mortality with a denominator of the disease incidence rate, not a denominator of total population...
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