Bipolar II: Not so different when co‐morbidity excluded

Subjects with unipolar depression and bipolar disorder types I and II who had been selected to be free of recent substance abuse and severe character pathology as part of their participation in two research studies, were compared on a number of clinical features. No significant differences were observed between bipolar I and II subjects on any of these measures. These results are consistent with the suggestion that previously reported differences between bipolar I and II might be attributable in part to the presence of character pathology and substance abuse in unselected bipolar II populations. Depression 3:154–156 (1995).