The Cycle of Classification: DSM-I Through DSM-5 - part 2

Blashfield, R. K., Keeley, J. W., Flanagan, E. H., & Miles, S. R. (2014). The Cycle of Classification: DSM-I Through DSM-5. Annu. Rev. Clin. Psychol, 10, 25-51

Allen Frances, M.D DSM 5 Is Guide Not Bible—Ignore Its Ten Worst Changes.  https://www.psychologytoday.com/blog/dsm5-in-distress/201212/dsm-5-is-guide-not-bible-ignore-its-ten-worst-changes

This is part two of the post the Cycle of Classification: DSM-I Through DSM-5  published on June 23, 2016.

DSM4

DSM4 was published in 1994.  A major change from previous editions was the inclusion of a clinical significance criterion to almost half of all the categories, which required that symptoms cause "clinically significant distress or impairment in social, occupational, or other important areas of functioning".

DSM4TR

DSM4TR was published in 1994.  The diagnostic categories and most of the specific criteria for diagnosis were not changed in this edition.

In 2005 Sadler published an important and influential book titled "Values and Psychiatric Diagnosis".  Sadler highlighted five values and the roles they play in psychiatric nosology: (a) aesthetics—how people prefer things to be, in the sense that they “like” or “appreciate” them; (b) epistemology—choices about how we know what we know about classification (i.e., what research methods we prefer); (c) ethics—what morals the classification upholds; (d ) ontology—what is the fundamental nature of “things,” or in the case of psychiatry, what mental disorders are in a (meta)physical sense; and (e) pragmatics—how useful or user-friendly the classification might be. Until the publication of this book, most (although not all) of those assumptions were ignored or taken for granted. This book legitimized the imperative role philosophical discourse plays in the development of a classification of mental disorders.

DSM5

DSM5 was published in 2013, but the process of its development began in 1999.  Its drafts were published on an internet site, allowing people to remark and make suggestions.  The purpose of the DSM5 task force was to match the classification system to modern molecular biology, cognitive and affective neuroscience, and psychometrics.  The suggested categories were tested in eleven medical centers.  The total number of diagnostic categories in this classification system increased markedly. Most of this increase was in categories which covered a vast range of reasons why someone might be seen by a mental health professional (e.g., “overweight or obesity,” “problems related to unwanted pregnancy”).

The axes system that existed since the DSM3 was cancelled.  DSM5 has three parts:

Part one describes the structure of the DSM5.

Part two describes the mental disorder categories.  Significant changes in the fifth edition are the deletion of the subtypes of schizophrenia and the deletion of the subsets of autistic spectrum disorder.  The chapter that included disorders first diagnosed in infancy, childhood or adolescence was also deleted.

The third part introduces innovative models and measurement tools. Among them is an alternative model for personality disorders, which is a hybrid model (categorical and dimensional). There was a debate during the period preceding the DSM5 whether and how dimensional models of personality can be integrated into the DSM.  One of these models is the BIG5 model, about which I had briefly written before. 

Mental health professionals and the British Psychological Society argue that "normal" and "abnormal" personalities are not separate but exist on the same continuum.  It's possible to classify an "abnormal" personality by the same BIG5 factors.  It was suggested that the categories of personality disorders in the DSM5 be replaced by dimensional models of personality.  Blashfield and Keeley write that the political pressures against such a significant change were powerful, and the next version of the proposal involved a hybrid of categories and dimensions.  Some people argued that adopting a dimensional model of personality was not in the financial interest of the APA because copyrights for existing measurement instruments for these dimensions were held by others.

Other DSM5 criticisms:

The way the categories were built:  the DSM deals mainly with the symptoms of mental disorders and not with their causes.  It classifies disorders based on statistical or clinical patterns.  This method can cause the classification of people who have the same symptoms for different reasons or due to different causes into the same category.  This encumbers research efforts.  But what's the alternative?  I'm not sure we have enough knowledge to enable us to classify mental disorders according to their causes.

Over-diagnosis and medicalization of normal life situations:  some professionals argue that the great increase in the number of diagnostic categories reflects and causes an increased medicalization of human nature, and may cause over-diagnosis of mental disorders.  One of the people arguing this is Dr. Allen Frances, the head of the task force of the DSM4.  He argues that normal life situations, like temper tantrums or natural grief, become mental disorders in the DSM5. 

  

The extent to which the DSM structure is in line with the way clinicians diagnose in real life: Research about the way experienced clinicians make diagnostic decisions show that they are not using criteria lists.  Instead they compare the new patient with patients they have seen previously using a prototype.  Thus some professionals argue that the DSM diagnostic criteria fit research more than clinical practice (but see one of the previous points…).   Blashfield and Keeley suggest that prototypes would be a better way for clinicians to learn and communicate diagnostic categories once the categories are well defined with feature lists (i.e., criteria).

The DSM5 writing process:  controversy erupted over the potentially secretive process that was being used to make decisions as well as the corrupting influence of income and the DSM's potential revenues. More than once, important decisions that affected the final outcome of a DSM categorization system were made at the level of the Board of Trustees of the APA. 

Blashfield and Keeley recommend that the APA make all financial records about the DSM, both past and present, publicly available. This would include information about royalties (if any) and honoraria paid to individuals involved with these editions and funding from pharmaceutical or other companies that could experience a financial impact because of DSM-influenced decisions.