Does testing for bimodality clarify whether the bipolar disorders are categorically or dimensionally different to unipolar depressive disorders?

Akiskal, 2006, The DSM-IV and ICD-10 categories of recurrent [major] depressive and bipolar II disorders: evidence that they lie on a dimensional spectrum, Journal of Affective Disorders, 92, 45, 10.1016/j.jad.2005.12.035 Cassano, 2004, The mood spectrum in unipolar and bipolar disorder: arguments for a unitary approach, The American Journal of Psychiatry, 161, 1264, 10.1176/appi.ajp.161.7.1264 Hirschfeld, 2000, Development and validation of a screening instrument for bipolar spectrum disorder: the mood disorder questionnaire, The American Journal of Psychiatry, 157, 1873, 10.1176/appi.ajp.157.11.1873 Parker, 1983, Old data, new interpretation: a re-analysis of Sir Aubrey Lewis' MD thesis, Psychological Medicine, 23, 859, 10.1017/S0033291700026349 Parker, 1996 Parker, 2006, The Black Dog Institute Depression Clinic: a sub typing model in practice, Australia Psychiatry, 14, 300, 10.1080/j.1440-1665.2006.02289.x Phelps, 2008, Validity and utility of bipolar spectrum models, Bipolar Disorders, 10, 179, 10.1111/j.1399-5618.2007.00562.x Plummer, 2010 Wilcox, 1981, A review of the beta-binomial model and its extensions, Journal of Educational and Behavioral Statistics, 6, 3, 10.3102/10769986006001003 Williams, 1994, Hypomania Interview Guide (including hyperthymia) Zimmerman, 2009, Performance of the mood disorders questionnaire in a psychiatric outpatient setting, Bipolar Disorders, 11, 759, 10.1111/j.1399-5618.2009.00755.x