[The potential of psychopathological symptoms to differentiate diagnostic groups (author's transl)].

We investigated the extent psychiatric illnesses can be differentiated by means of psychopathological symptoms. The present condition of 2269 patients was analyzed; they had been admitted to the psychiatric clinic of the Free University of Berlin during 1971-1976, as documented by the AMP (PAS) documentation system. The most frequent diagnosis in the sample was schizophrenia (32%), followed by neurosis (22%), affective psychosis (14%), addiction (6.7%), and organic psychosis (6.2%). We could demonstrate that even such diagnostic groups are usually discernible by symptoms, where the differential diagnosis is often difficult. Organic psychosis vs paranoid schizophrenia and depressive neurosis vs depressive psychosis can be determined, but manic syndromes in schizoaffective psychosis vs manic syndromes in affective psychosis are hardly discernible. The potential to differentiate, however, only pertains to diagnostic groups, since many individual patients cannot accurately be classified into diagnostic groups by psychopathological symptoms alone. Only a few symptoms are pathognomonic, and if there are pathogomonic symptoms characterizing a diagnostic group, only a few patients in this group show these symptoms. These results indicate, at least for the high number of patients without severe and typical symptomatology, that we must: 1. Achieve better differentiation on the diagnostic axis "psychopathology" by means of empirically derived syndromes instead of isolated symptoms. 2. Use other diagnostic axes (like etiology and course) for differential diagnostic purposes.