A lot of this stems from the fact that health IT systems aren't interoperable. Take a look at Epic Systems (the leading vendor). They code in MUMPS, which predates C as a language.

I'm exploring a startup in data analytics for behavioral health, and there it's even worse. Unlike blood pressure or cholesterol, everything is based on intuition. It's what Vinod Khosla means when he refers to modern medicine as being like witchcraft.