http://en.wikipedia.org/wiki/DSM-IV_Codes
Control + F Bipolar or click on it (This is what the insurance companies see as part of the bipolar spectrum if you're curious)

I'm diagnosed as 296.80 which means I'm considered BP NOS. According to wiki (i've seen it elsewhere) most people fit the description for this rather than fully fitting into either BP I or BP II. It's basically a catch-all for people who have a mood disorder that isn't depression. NOS can vary in severity. (There is also mood disorder NOS which I was diagnosed before hospitalization)

It shows that they only really have a rudimentary understanding of the disorder because it shows itself in many different ways that are met by elevated and lowered mood. (Which is probably the only thing that is definite about bipolar disorder)