article in Acta Psychiatrica Scandinavica, of which one of the authors is Nassir Ghaemi (whom I have mentioned before eg. see post), says that the claim of overdiagnosis of bipolar disorder is mistaken. True, the paper which is commonly quoted to substantiate this point also found considerable underdiagnosis. Of 145 patients who reported they had had a previous diagnosis of bipolar disorder, only 63 were diagnosed as such using the Structured Clinical Interview for DSM-IV (SCID). But there were also another 27 patients picked up on SCID that had not had that diagnosis.
The article uses these figures to argue that bipolar disorder is mainly underdiagnosed. This is motivated by the authors' belief that antidepressants are not very effective in bipolar depression and these people would do better on mood stabilisers. However, the dispute about the significance of the figures misses the main point about the validity of bipolar II disorder. Has the diagnosis of bipolar disorder been extended too far to include people who would not necessarily have been seen on that spectrum (see previous post)?