New directions in diagnosis: the longitudinal processes of schizophrenia.

Kraepelin's description of "dementia praecox" was a synthesizing influence in a field that had for too long been fragmented in its thinking about severe psychiatric disorders. Now, once again, the field is attempting to deal with some of the complexities involved in psychopathology and its evolution, complexities that have been reemphasized by newer descriptive research methods. To account for patients deviations from stereotyped diagnostic and prognostic concepts, multiple aspects of course of disorder have been defined and principles of multiaxial diagnosis supported. These principles can provide a basic structure for practice and research using a biopsychosocial orientation within the context of a system model.