On the periodicity of manic-depressive insanity, by Eliot Slater (1938): translated excerpts and commentary

Oepen, Godehard; Baldessarini, Ross J.; Salvatore, Paola

doi:10.1016/S0165-0327(02)00359-2

« Previous Next »Journal of Affective Disorders
Volume 78, Issue 1 , Pages 1-9, January 2004

On the periodicity of manic-depressive insanity, by Eliot Slater (1938): translated excerpts and commentary

Godehard Oepen
- Department of Psychiatry and Behavioral Neurobiology, UAB School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA
- International Consortium for Bipolar Disorder Research, Department of Psychiatry and Neuroscience Program, Harvard Medical School, Boston, MA, and the Bipolar and Psychotic Disorders Program, McLean Division of Massachusetts General Hospital, Belmont, MA 02478-9106, USA
Ross J. Baldessarini
- International Consortium for Bipolar Disorder Research, Department of Psychiatry and Neuroscience Program, Harvard Medical School, Boston, MA, and the Bipolar and Psychotic Disorders Program, McLean Division of Massachusetts General Hospital, Belmont, MA 02478-9106, USA
- Corresponding author. Mailman Research Center, McLean Hospital, 115 Mill Street, Belmont, MA 02478-1906, USA. Tel.: +1-617-855-3203; fax: +1-617-855-3479.
Paola Salvatore
- International Consortium for Bipolar Disorder Research, Department of Psychiatry and Neuroscience Program, Harvard Medical School, Boston, MA, and the Bipolar and Psychotic Disorders Program, McLean Division of Massachusetts General Hospital, Belmont, MA 02478-9106, USA
- Psychiatric Clinic of the University of Parma, Parma, Italy

Received 15 March 2002; accepted 15 August 2002.

Abstract

Since the classic descriptions of the course of bipolar and recurrent depressive forms of manic-depressive illness by Emil Kraepelin a century ago, it has been considered a truism that the rate of cycling increases, and wellness intervals shorten, with rising counts of recurrences, particularly early in the natural history of the illness. Less well known is that the analysis of this phenomenon is vulnerable to a computational artifact first described by Eliot Slater, based on his reanalysis of data from manic-depressive patients first evaluated by Kraepelin at the Munich Psychiatric Institute. Slater realized that there is an increasingly disproportionate representation of faster-cycling patients in sub-samples involving higher cycle-counts in pooled samples of subjects. More accurate results require analyzing illness-course either within individuals, or in groups matched for episode-counts. This artifact is pervasive in the older and modern research literature, but still not widely recognized. Since Slater’s 1938 report in German is not well known, we provide an abbreviated English translation with commentary and additional reanalysis to highlight the phenomenon that might be termed ‘Slater’s Fallacy’.

Keywords: Bipolar disorder, Cycles, Kindling, Manic-depressive, Periodicity, Progressive course, Kraepelin, Sensitization, Slater, Wellness intervals