Purpose. This paper studies how diagnosis is currently conceptualized in the field of psychiatry, and examines whether this mode of diagnosis is relevant for psychotherapeutic intervention.
Method. Narrative literature review was used in this study.
Results. In the context of the DSM, diagnosis is equated with classification. Symptoms and complaints are approached in terms of a medical semiological model, and are seen as signs of underlying illness processes. In discussing this approach the author makes use of Gottlob Frege's theory, in which three aspects of a sign are discerned: the reference/referent or Bedeutung, the sense or Sinn, and the representation/idea or Vorstellung. Based on this distinction, it is argued that in the transition from the DSM-III to the DSM-5 much effort has been taken to disambiguate the sense attributed to symptoms and complaints, while person-specific ideas and representations have been excluded. This exclusion of the Vorstellung is criticized, both from a psychiatric and a psychotherapeutic perspective. Subsequently it is argued that whereas the DSM-III and DSM-IV avoided strong statements on etiology, the DSM-5 makes clear choices. The DSM-5, and more recently the RDoC group within the NIMH, aims at developing systems of classification that start from the assumption that psychiatric disorders are brain disorders. It is argued that by doing so a referent is classified that is different from the object of intervention that psychotherapeutic theories are concerned with.
Conclusion. Such a view of diagnosis is not workable for psychotherapy. The exclusion of personal experiences associated with symptoms and complaints is problematic and the referent that recent psychiatric classification uses, that is, brain processes, is not compatible with the referent that psychotherapeutic theories use. Case formulation can be seen as an alternative to standard classification.