ABSTRACT
Diagnostic schemes for bipolar disorder provide greater benefit for investigations in disease epidemiology, comorbidity, pathophysiology, and treatments than do those of most psychiatric disorders. Some of these benefits have been realized in previous studies. Others are now ready for implementation. Yet other potential benefits may not be realized without certain changes in official Diagnostic and Statistical Manual (DSM) criteria. I review here the strengths and weaknesses of current criteria and extension criteria that may be used beneficially to subclassify bipolar patients. Additionally, I address the potential for dimensional behavioral assessment in contrast to the strictly syndromal criteria of DSM, 4th edition (DSM-IV), for biological studies.
