HISTORICALLY, psychiatry has emphasized phenomenologic description in its conceptualization and characterization of schizophrenia. Although Kraepelin1 and Langfeldt2 included longitudinal course as a diagnostic criterion, most students of schizophrenia focused on qualitative descriptions of the psychopathologic processes. Initial efforts to define the disorder by its neurobiologic characteristics were frustrated by the inability of classical neuropathologists to identify histopathologically distinct and replicable lesions.3,4 Given the variable nature of the disorder, clinicians attempted to reduce its heterogeneity by delineating meaningful subtypes. The traditional subtypes of paranoid, undifferentiated, hebephrenic (disorganized), and catatonic schizophrenia were defined by qualitative differences in psychopathologic features and have endured despite the absence of validating evidence from investigations of treatment response, long-term outcome, pathophysiologic processes, or genetics. However, reductio ad absurdum, some skeptics suggest that phenomenological distinctions in schizophrenia may be meaningless in our efforts to understand the underlying nature and cause of the disease.
Lieberman JA. Signs and SymptomsWhat Can They Tell Us About the Clinical Course and Pathophysiologic Processes of Schizophrenia?. Arch Gen Psychiatry. 1995;52(5):361-363. doi:10.1001/archpsyc.1995.03950170035005