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The validity and internal structure of the Bipolar Depression Rating Scale: data from a clinical trial of N-acetylcysteine as adjunctive therapy in bipolar disorder

Published online by Cambridge University Press:  24 June 2014

Michael Berk*
Affiliation:
Department of Clinical and Biomedical Sciences: Barwon Health, The University of Melbourne, Geelong, Australia Orygen Research Centre, Parkville, Australia Mental Health Research Institute, Parkville, Australia
Seetal Dodd
Affiliation:
Department of Clinical and Biomedical Sciences: Barwon Health, The University of Melbourne, Geelong, Australia
Olivia M Dean
Affiliation:
Department of Clinical and Biomedical Sciences: Barwon Health, The University of Melbourne, Geelong, Australia Mental Health Research Institute, Parkville, Australia
Kristy Kohlmann
Affiliation:
Department of Clinical and Biomedical Sciences: Barwon Health, The University of Melbourne, Geelong, Australia
Lesley Berk
Affiliation:
Department of Clinical and Biomedical Sciences: Barwon Health, The University of Melbourne, Geelong, Australia Department of Psychiatry, University of Melbourne, Parkville, Australia
Gin S Malhi
Affiliation:
Academic Discipline of Psychological Medicine, Sydney Medical School, University of Sydney, Sydney, NSW, Australia CADE Clinic, Department of Psychiatry, Royal North Shore Hospital, Sydney, NSW, Australia
*
Michael Berk, Department of Clinical and Biomedical Sciences: Barwon Health, The University of Melbourne, PO Box 281, Geelong 3220, Australia. Tel: +61 3 5260 3085; Fax: +61 3 5246 5165; E-mail: [email protected]

Abstract

Berk M, Dodd S, Dean OM, Kohlmann K, Berk L, Malhi GS. The validity and internal structure of the Bipolar Depression Rating Scale: data from a clinical trial of N-acetylcysteine as adjunctive therapy in bipolar disorder.

Background:

The phenomenology of unipolar and bipolar disorders differ in a number of ways, such as the presence of mixed states and atypical features. Conventional depression rating instruments are designed to capture the characteristics of unipolar depression and have limitations in capturing the breadth of bipolar disorder.

Method

The Bipolar Depression Rating Scale (BDRS) was administered together with the Montgomery Asberg Rating Scale (MADRS) and Young Mania Rating Scale (YMRS) in a double-blind randomised placebo-controlled clinical trial of N-acetyl cysteine for bipolar disorder (N = 75).

Results:

A factor analysis showed a two-factor solution: depression and mixed symptom clusters. The BDRS has strong internal consistency (Cronbach's alpha = 0.917), the depression cluster showed robust correlation with the MADRS (r = 0.865) and the mixed subscale correlated with the YMRS (r = 0.750).

Conclusion:

The BDRS has good internal validity and inter-rater reliability and is sensitive to change in the context of a clinical trial.

Type
Research Article
Copyright
Copyright © 2010 John Wiley & Sons A/S

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References

Mitchell, PB, Wilhelm, K, Parker, G, Austin, MP, Rutgers, P, Malhi, GS.The clinical features of bipolar depression: a comparison with matched major depressive disorder patients. J Clin Psychiatry 2001;62:212216; quiz 217.CrossRefGoogle ScholarPubMed
Ghaemi, SN, Ko, JY, Goodwin, FK.“Cade's disease” and beyond: misdiagnosis, antidepressant use, and a proposed definition for bipolar spectrum disorder. Can J Psychiatry 2002;47:125134. CrossRefGoogle Scholar
Hamilton, M.Development of a rating scale for primary depressive illness. Br J Soc Clin Psychol 1967;6: 278296. CrossRefGoogle ScholarPubMed
Montgomery, SA, Asberg, M.A new depression scale designed to be sensitive to change. Br J Psychiatry 1979;134:382389. CrossRefGoogle ScholarPubMed
Berk, M, Malhi, GS, Mitchell, PBet al. Scale matters: the need for a Bipolar Depression Rating Scale (BDRS). Acta Psychiatr Scand Suppl 2004;442:3945. CrossRefGoogle Scholar
Chang, JS, Ahn, YM, Yu, HYet al. Exploring clinical characteristics of bipolar depression: internal structure of the bipolar depression rating scale. Aust N Z J Psychiatry 2009;43:830837. CrossRefGoogle ScholarPubMed
Berk, M, Malhi, GS, Cahill, Cet al. The Bipolar Depression Rating Scale (BDRS): its development, validation and utility. Bipolar Disord 2007;9:571579. CrossRefGoogle ScholarPubMed
Berk, M, Copolov, DL, Dean, Oet al. N-acetyl cysteine for depressive symptoms in bipolar disorder – a double-blind randomized placebo-controlled trial. Biol Psychiatry 2008;64:468475. CrossRefGoogle ScholarPubMed
Sheehan, DV, Lecrubier, Y, Sheehan, KHet al. The Mini-International Neuropsychiatric Interview (M.I.N.I.): the development and validation of a structured diagnostic psychiatric interview for DSM-IV and ICD-10. J Clin Psychiatry 1998;59 (Suppl. 20):2233; quiz 34–57.Google ScholarPubMed
Kruskal, JB.Multidimensional scaling by optimizing goodness-of-fit to a nonmetric hypothesis. Psychometrika 1964;29:2842. CrossRefGoogle Scholar
Kruskal, JB, Wish, M.Multidimensional scaling. Newbery Park, CA: SAGE, 1978. CrossRefGoogle Scholar