Empirically And Etiological-Based Nosology

Rethinking the Classification of Psychological Disorders:

Towards an Empirically and Etiologically Based Nosology

Abstract:

Rethinking the Classification of Psychological Disorders:

Towards an Empirically and Etiologically Based Nosology

In the United States, the Diagnostic and Statistical Manual of Mental Disorders (DSM, American Psychiatric Association [APA], 2013) presents the primary nosological structure for understanding constellations of mental health grievances as psychological disorders. The DSM puts forth a universal vocabulary that allows researchers, clinicians, healthcare workers, and policy makers to understand that a patient presenting with feelings of overwhelming sadness, trouble sleeping, difficulty concentrating,

It is intentionally atheoretical; rather, it classifies disorders descriptively, on the basis of co-occurring symptoms agreed to be phenomenologically distinct categories. Such categories are defined by polythetic criteria, but held to represent distinct entities, separate from other psychological disorders and representative of functional departures from normality and sub-threshold symptom presentations (look for citations in beginning DSM pages). Although the DSM aims to be agnostic with regards to the etiology of psychological disorders, I argue that the classification of symptom constellations as phenomonically distinct categories has, for utilizers of the system, given rise to the implicit assumption that these categories develop out of distinct etiologies. Furthermore, I maintain that we now have sufficient evidence for abandoning the current rationally based approach in favor of empirically based diagnostic classification system that reflects actual covariance among symptoms and is sensitive to symptom

[Define comorbidity?] The separation of disorders into distinct categories implies that these constructs ought to be meaningfully distinct; however, in the population, these disorders co-occur at rates far greater than chance (cite). In fact, there is now considerable evidence to suggest that comorbidity is more the rule than the exception (cite), and that such comorbidity is often substantial ([maybe add more, “e,g., individuals carrying an average of X concurrent diagnoses;” cite) Moreover, such comorbidity not random; rather, certain disorders or classes of disorders appear to covary systematically across the population (cite). Reliable patterns of comorbidity indicate the presence of shared latent factors underlying hypothetically distinct diagnostic