The variable results of positive-negative research with schizophrenics underscore the importance of well-characterized, standardized measurement techniques. We report on the development and initial standardization of the Positive and Negative Syndrome Scale (PANSS) for typological and dimensional assessment. Based on two established psychiatric rating systems, the 30-item PANSS was conceived as an operationalized, drug-sensitive instrument that provides balanced representation of positive and negative symptoms and gauges their relationship to one another and to global psychopathology. It thus constitutes four scales measuring positive and negative syndromes, their differential, and general severity of illness. Study of 101 schizophrenics found the four scales to be normally distributed and supported their reliability and stability. Positive and negative scores were inversely correlated once their common association with general psychopathology was extracted, suggesting that they represent mutually exclusive constructs. Review of five studies involving the PANSS provided evidence of its criterion-related validity with antecedent, genealogical, and concurrent measures, its predictive validity, its drug sensitivity, and its utility for both typological and dimensional assessment.

Positive and negative syndromes were studied in relation to demographic, historical, genealogical, clinical, psychometric, extrapyramidal, and follow-up measures of 101 chronic schizophrenic patients. The criterion scales proved to be reliable, normally distributed, and strongly correlated with general psychopathology, but otherwise inversely related to one another. Multiple regression analysis identified sets of 4-6 independent variables that explained 74%-81% of the scales' variance. A positive syndrome was associated chiefly with productive features, family history of sociopathy, more previous hospital admissions, and longer in-patient stay during the 30-month follow-up period. A negative syndrome correlated with deficits in cognitive, affective, social, and motor spheres, higher incidence of major psychiatric illness but less affective disorder among relatives, lower education, and greater cognitive developmental impairment. The results underscore the importance of genetic and biodevelopmental variables for understanding schizophrenic syndromes.