The folks at SoftwareAdvice.com recently published EHR vs. EMR – What’s the Difference?
It’s a good, but at times too high-level and could have been a bit more substantive in terms of real problems and potential solutions (but I suspect this was "landscape" summary so I can’t fault them too much). It talks about what is an EMR, EHR, and PHR from a definitional perspective and goes on to give a good summary of how often each term is used (with Google stats) and why vendors are still calling themselves EMRs.
I think the general debate of whether it’s an electronic health record (EHR) versus an electronic medical record (EMR) or a personal health record (PHR) is really silly. It’s like saying that your bank records kept at the bank versus the copy they give you at home via online banking versus what you see at the ATM versus what you put into Quicken are all somehow different records — they are not. They are the same financial record (yours!).
EHRs, EMRs, PHRs, are all views of a single person’s health record that doesn’t really exist anywhere in totality — they are simply slices. Thinking that we’ll ever have a comprehensive record for anyone is like saying there’s one comprehensive financial record for a person that would include their taxes, bank statements, 401k statements, etc. There are aggregators like Mint.com and Yodlee.com that do financial data aggregation because there is no single source for a financial record and there never will be (too many players).
Healthcare data is far more detailed and even more volumnious and far harder to aggregate. Good luck trying to unify these definitions.