Basic symptoms and their contribution to the differential typology of acute schizophrenic and schizoaffective disorders.

One hundred and fifty male inpatients - 128 patients with DSM-IV schizophrenia and 22 patients with DSM-IV schizoaffective disorder - were investigated, over the course of their acute psychosis, on whether there were differences in the extent of basic symptoms (measured by the Bonn Scale for the Assessment of Basic Symptoms) according to their diagnostic subtype. Another aim was to find out if the diagnostic subtypes could be discriminated by means of basic symptoms and if clusters gained from basic symptoms were in accordance with the diagnostic subtypes. Differences in basic symptoms were found between the subtypes, but a clear discrimination of diagnostic subtypes by means of basic symptoms could not be achieved. There was indication that patients with prominent delusions or auditory hallucinations reported more basic symptoms than patients with exclusively prominent disorganization.