I wonder how accurate these international rankings are. Recently someone claimed that infant mortality was worse in the U.S. than in Cuba, something I find difficult to believe without additional explanation.
Anyway, in the case of the United States, the national averages, rankings, and indexes really don't mean very much. The U.S. is a very big country with great economic diversity. Real estate costs more in NYC, but salaries are higher, for example. Crime and disease are often much higher in ghetto areas than most suburban areas.
Advocates of public policy on both sides of the aisle love to throw out statistics. Newspapers like them as well -- they "authenticate" a story. But the key component of all statistics is the base sample. When we say 25% percent of such-and-such, we need to understand exactly what 'such and such' _includes_ AND _excludes_, as well as exactly the definition of the subset percentage. Further, it is critical that statistics be compared in context to other yardsticks of other equivalent areas and situations of past time. Often the full story is not told.