Is disorder x in category or spectrum y? General considerations and application to the relationship between obsessive–compulsive disorder and anxiety disorders


  • Dan J. Stein M.D. Ph.D.

    Corresponding author
    1. Department of Psychiatry and Mental Health, University of Cape Town, Cape Town, South Africa
    2. Department of Psychiatry, Mt. Sinai School of Medicine, New York
    • UCT Department of Psychiatry and Mental Health, Groote Schuur Hospital, J-2, Anzio Road, Observatory 7925, South Africa
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Is obsessive–compulsive disorder (OCD) best categorized as an anxiety disorder? This question has been raised previously, but advances in the psychobiology of OCD and the anxiety disorders, and preparations for Diagnostic and Statistical Manual of Mental Disorders—V and International Classification of Diseases—11, make reconsideration timely. The debate in turn raises the more general issue of how best to address any question of the form “is disorder x in category or spectrum y?” Such questions are related to a number of key debates in philosophy of science and language and have also increasingly been addressed by the cognitive–affective neuroscience of categorization. Here, we review this background debate and use OCD as a relevant exemplar. Depression and Anxiety 25:330–335, 2008. © 2008 Wiley-Liss, Inc.