I recently acquired my psychiatric records for transfer to a new doctor out-of-state. I thought I was Bipolar II, but the diagnosis my psychiatrist wrote every visit was Mood NOS (R/O bipolar).

What does that mean? I know the "Mood NOS" indicates a mood disorder not defined in the DSM-IV, but was he trying to rule out bipolar every time he saw me? In this context, does "R/O" really mean something more like "maybe?"

I'm confuzzed.