An understanding of statistics is essential if a physician, or any interested party, is to understand the medical literature. Alas asking a typical doctor to evaluate statistical data is like giving a scalpel to an accountant and asking him to perform a coronary bypass. My last post on sodium intake gave an example of inadequate data interpretation. Here’s another.
A study, again in the JAMA, Health Care Spending in the United States and Other High-Income Countries, looks at what the title depicts. It points out that we spend much more than any other country in the world on medical care. This is undeniably true. It then goes on to imply that we are not getting our money’s worth because outcomes here are worse than in other developed countries. Two of these, which are commonly cited ad nauseum, are infant mortality and life expectancy. They are said to be worse in the US compared to other developed countries.
I’ll get back to these two markers in a moment. Medical care in the US costs about twice as much as it should because of our bizarre marriage of private and government funding which has produced a horribly deformed offspring. Everything about this monstrous child conspires to raise costs. It allows no market forces which could constrain costs. These outrageous prices will continue to rise until this multi-trillion dollar baby dies from overfeeding.
But infant mortality and life expectancy are not indicators of poor medical care in the US compared to other delivery systems. We’ve known for generations that infant mortality rates are differently reported across national borders making comparisons virtually meaningless. For example, if one looks at neonatal mortality in infants weighing more than 1000 g our rates are better than the UK, Denmark, The Netherlands, and Canada. These and other developed countries do not make the same effort to save infants less than 1000 g as do we and they also often don’t include them when they die as do we. This both make our care more expensive and our mortality rates look worse.
So I’ll concentrate on life expectancy which is easier to analyze. The US has the lowest life expectancy of any developed country – see chart below. Click on it to enlarge it.
Comparing a country as large and populous as the US with others less diverse and smaller than the US is riff with selection bias. Consider Mormons living in Utah (a 2004 study). Life expectancy was 77.3 years for LDS (Mormons) males, 70.0 for non-LDS males, 82.2 for LDS females, and 76.4 for non-LDS females. For those alive at age 80, the remaining years of life on average were 8.2 for LDS males, 6.5 for non-LDS males, 10.3 for LDS females, and 7.1 for non-LDS females. Only a small portion of the difference in life expectancy was explained by differences in tobacco use. I doubt that any of this difference in survival is attributable to the quality of or the access to medical care.
The country with the longest life expectancy is Japan. Examining this datum is very interesting. The reasons for this superior survival are unclear. If better medical care was a prominent factor than the survival of Japanese-Americans should be worse than their cousins who remained in Japan. The reverse appears to be the case. Data on Japanese-Americans specifically are not current or are unavailable. But data on all Asian-Americans which obviously includes Japanese-Americans are at hand. Their life expectancy is 86.7 years exceeding that of Japan by almost three years. In females it’s 88.9 years, while for males its 84.1. Thus Asian-Americans, putatively the victims of our “poor” medical system, live longer than any other group in the world including their Asian relatives who stayed put. In six states life expectancy in Asian-American females is greater than 90.
My point is that among developed countries differences in life expectancy have little or nothing to do with medical care regardless of how cost effective it may or may not be, but rather reflect the cultural, social, and genetic characteristics of the populations served. Those with an axe to grind should sharpen it elsewhere.