Definition, diagnosis, and differentiation

It is the thesis of this paper that the DSM-III-R personality disorder criteria sets attempt to serve conflicting purposes: (a) to define the disorder, (b) to diagnose the presence of the disorder, and (c) to differentiate one disorder from another. Some features are useful for defining, diagnosing, and differentiating, but many will be optimal for only one of these functions. Related issues concern the relationship of the criteria to the disorder's phenomenology versus pathology, the optimal specificity of the criteria set, and the emphasis on inclusion versus exclusion criteria. It is suggested that DSM-IV: (a) provide a description of the personality disorder's phenomenology separate from the diagnostic criteria, with the latter varying across time, setting, and situations; (b) present the criteria at the level of trait constructs, with prototypic acts provided to illustrate the meaning of the construct; (c) provide an independent set of criteria for differential diagnosis; and (d) provide exclusion as well as inclusion criteria.