The material detailed in this paper was first presented at the Festschrift for Professor Gordon Parker in September 2025. One of Gordon’s main areas of research has been bipolar disorder. This paper first addresses general aspects of Gordon’s approach to research, before focussing on themes within his bipolar disorder research portfolio, in particular phenomenology, bipolar II disorder, the distinction between borderline personality disorder and bipolar II disorder, and treatments for bipolar II disorder, particularly lamotrigine.
ParkerG. Psychiatric diagnosis in New South Wales compared to England and Wales. Br J Psychiatry1975; 127: 556–558. https://doi.org/10.1192/bjp.127.6.556
ParkerGHadzi-PavlovicDWilhelmK, et al.Defining melancholia: properties of a refined sign-based measure. Br J Psychiatry1994; 164(3): 316–326. https://doi.org/10.1192/bjp.164.3.316
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ParkerGRoyKWilhelmK, et al.The nature of bipolar depression: implications for the definition of melancholia. J Affect Disord2000; 59(3): 217–224. https://doi.org/10.1016/s0165-0327(99)00144-5
ParkerGGrahamRSynnottH, et al.Is the DSM-5 duration criterion valid for the definition of hypomania?J Affect Disord2014; 156: 87–91. https://doi.org/10.1016/j.jad.2013.11.020
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ParkerG. Bipolar II disorder: once missed, now dismissed, time to resist. Bipolar Disord2022; 24(6): 574–579. https://doi.org/10.1111/bdi.13174
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ParkerGRicciardiTTavellaG, et al.A single-blind randomized comparison of lithium and lamotrigine as maintenance treatments for managing bipolar II disorder. J Clin Psychopharmacol2021; 41(4): 381–388. https://doi.org/10.1097/JCP.0000000000001424
11.
SpoelmaMJLeidreiterJBayesA, et al.A naturalistic effectiveness study of maintenance therapies for the bipolar disorders. Acta Psychiatr Scand2024; 149(2): 98–109. https://doi.org/10.1111/acps
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BayesAParkerGParisJ. Differential diagnosis of bipolar II disorder and borderline personality disorder. Curr Psychiatry Rep2019; 21(12): 125. https://doi.org/10.1007/s11920-019-1120-2
