Doctors Per 1 000 population

In my previous post on the healthcare composition in the US, I had cited a CDC report as claiming that "[p]hysician and clinical services accounted for 23.5% of total personal health care expenditures".

So in order to understand what drives these physican costs, I asked myself the following: Is there a shortage of doctors in the US? Could that be why physician costs are so high?

So I looked up the doctors per 1 000 population datum over at this OECD site.

This is 2009 data, so I don't know how things may have changed in the last 7 years or so.

I don't know how to interpret this data. In one sense, US does appear towards the bottom of the list. On the other hand, countries like Japan that have even less doctors (per 1000 population) have less healthcare costs.