Stability of the diagnosis of deficit syndrome in schizophrenia.

Abstract

Primary, enduring negative symptoms have been distinguished from negative symptoms more generally and are used to define the deficit syndrome of schizophrenia. Although the validity of the deficit syndrome has been demonstrated by using brain imaging, neuropsychological, illness outcome, and developmental history data, the stability of this diagnostic category has not been tested prospectively by using direct patient assessments. Forty-three outpatients with schizophrenia and schizoaffective disorder were categorized into deficit and nondeficit groups an average of 3.8 years after having been previously categorized. There was 83% agreement between initial and blind follow-up designations of deficit status and 88% agreement on the nondeficit categorization. These results provide evidence for the long-term stability of the deficit syndrome in patients with schizophrenia and the reliability of the deficit/nondeficit categorization when diagnosed by those with appropriate training. Furthermore, they validate the method of categorizing deficit patients by using cross-sectional and retrospective data.