[On the diagnosis of schizophrenia (author's transl)].

After a review of terms used in the description of schizophrenia, mainly based on Bleuler's and Kurt Schneider's terminology, attempts to operationalize the diagnosis of schizophrenia are discussed. First rank symptoms according to Kurt Schneider have been most extensively used as criteria. Classification based on these symptoms is, however, subject to certain restrictions from cross-sectional as well as longitudinal points of view. Additional criteria are necessary to describe the whole spectrum of what is called schizophrenia in clinical psychiatry with regard to better therapeutic measures. Symptomatology is also the leading criterion for the diagnosis of schizophrenia in the discussed multidimensional schemes. With an increasing number of criteria the diagnosis of schizophrenia will be confined according to the applied variables.