Just how many of those MRIs in the US are done without insurance or medicare - ie, are subjected to price rationing mechanisms?
Moreover, in a system like the US health care the "average" isn't very meaningful, because if you and I have a sore knee, and you get 2 MRIs per year, and I get none, well...
Moreover, in a system like the US health care the "average" isn't very meaningful, because if you and I have a sore knee, and you get 2 MRIs per year, and I get none, well...