Stability of positive and negative symptoms in schizophrenia.

Fifty-nine DSM-III-R schizophrenic outpatients were assessed for positive and negative symptoms using Andreasen's Scale for Assessment of Positive Symptoms (SAPS) and the Scale for Assessment of Negative Symptoms (SANS). Reevaluation of these patients 12 months later revealed a moderate degree of stability for both SAPS and SANS total scores and most of their subscales. Only the subscale scores for apathy and bizarre behaviour failed to show a significant correlation in stability in 12 months. The results are discussed in the context of the reported literature.