A Symptom Based Approach to the Diagnosis of Schizophrenia *

Abstract

This study reviews the attempts of Carpenter et al to develop valid diagnostic criteria of schizophrenia by means of a flexible 12 point system of signs and symptoms based on the IPSS. The authors applied the 12–point system to 67 inpatients and obtained different levels of certainty in identifying proportions of schizophrenic and non-schizophrenic patients: 80% of clinically diagnosed schizophrenic patients obtained 5 or more points. Kappa statistics revealed a 0.59 proportion of agreement in excess to chance between clinical and experimental diagnosis of schizophrenia, indicating the clinical usefulness of the 12 point system.