"Tn DSM-IV, there is no assumption that each category of mental disorder
I is a completely discrete entity with absolute boundaries dividing it from JL other mental disorders or from no mental disorder" (American Psychiatric Association [APA], 2000, p. xxxi). This carefully worded disclaimer, however, is somewhat hollow, as it is the case that "DSM-IV is a categorical classification that divides mental disorders into types based on criterion sets with defining features" (APA, 2000, p. xxxi). Researchers and clinicians, following this lead, diagnose and interpret the conditions presented in DSM-IV as disorders that are qualitatively distinct from normal functioning and from one another.
The question of whether mental disorders are discrete clinical conditions or arbitrary distinctions along dimensions of functioning is a long-standing issue (Kendell, 1975), but its significance is escalating with the growing recognition of the limitations of the categorical model (Widiger & Clark, 2000; Widiger & Samuel, 2005). "Indeed, in the last 20 years, the categorical approach has been increasingly questioned as evidence has accumulated that the so-called categorical disorders like major depressive disorder and anxiety disorders, and schizophrenia and bipolar disorder seem to merge imperceptibly both into one another and into normality . . . with no demonstrable natural boundaries" (First, 2003, p. 661). In 1999, a DSM-V Research Planning Conference was held under joint sponsorship of the APA and the National Institute of Mental Health (NIMH), the purpose of which was to set research priorities that would optimally inform future classifications. One impetus for this effort was the frustration with the existing nomenclature.
In the more than 30 years since the introduction of the Feighner criteria by Robins and Guze, which eventually led to DSM-III, the goal of validating these syndromes and discovering common etiologies has remained elusive. Despite many proposed candidates, not one laboratory marker has been found to be specific in identifying any of the DSM-defined syndromes. Epidemiologic and clinical studies have shown extremely high rates of comorbidities among the disorders, undermining the hypothesis that the syndromes represent distinct etiologies. Furthermore, epidemiologic studies have shown a high degree of short-term diagnostic instability for many disorders. With regard to treatment, lack of treatment specificity is the rule rather than the exception. (Kupfer, First, & Regier, 2002, p. xviii)
DSM-V Research Planning Work Groups were formed to develop white papers that would set an effective research agenda. The Nomenclature Work Group, charged with addressing fundamental assumptions of the diagnostic system, concluded that it will be "important that consideration be given to advantages and disadvantages of basing part or all of DSM-V on dimensions rather than categories" (Rounsaville et al., 2002, p. 12).
The purpose of this chapter is to review the DSM-IV categorical diagnosis. The chapter begins with a discussion of fundamental categorical distinctions, including the boundaries with normality and among the existing diagnoses (the boundary with physical disorders was discussed briefly in a prior version of this chapter; Widiger, 1997). Reasons for maintaining a categorical model will then be considered. The chapter concludes with a recommendation for an eventual conversion to a more quantitative, dimensional classification of mental disorders.
Was this article helpful?
Tips And Tricks For Relieving Anxiety... Fast Everyone feels anxious sometimes. Whether work is getting to us or we're simply having hard time managing all that we have to do, we can feel overwhelmed and worried that we might not be able to manage it all. When these feelings hit, we don't have to suffer. By taking some simple steps, you can begin to create a calmer attitude, one that not only helps you feel better, but one that allows you the chance to make better decisions about what you need to do next.