Is bipolar disorder usually misdiagnosed?

Dx.: I would say no to that. However, the diagnosis is often missed especially for bipolar ii disorder or bipolar disorder not otherwise specified. It can be especially difficult to diagnose in a young child.

Yes and no: Bipolar d/o is a longitudinal disorder. Someone with depression may not have had recognizable manic episodes. Manic episodes associated with psychosis may not be recognized as mania. Rarely would someone be misdiagnosed with bipolar d/o unless psychotic symptoms persist in the absence of significant mood related symptoms which would likely be schizophrenia. Substance abuse may cloud the picture.