Internal consistency, temporal stability and neuropsychological correlates of three cognitive components of the Positive and Negative Syndrome Scale (PANSS)

Comprehensive models of schizophrenia have increasingly included symptoms of cognitive dysfunction as an important feature of schizophrenia. Factor analytic studies of the Positive and Negative Syndrome Scale (PANSS) have consistently established cognitively disorganized symptoms as a separate domain from positive and negative symptoms. However, the individual symptom composition of the cognitive domain varies from model to model. The present study explores the temporal stability, internal consistency, concurrent validity, and discriminant validity for three published PANSS factor analytically derived cognitive components (Bell et al., 1994a. Psychiatry Res., 52, 295-303; Dollfus et al., 1991. fur. Psychiatry, 6, 251-259; Kay and Sevy, 1990. Schizophr: Bull., 16, 537-544). Analyses were conducted using PANSS data from 120 patients with DSM-IV diagnoses of schizophrenia or schizoaffective disorder. Results indicate that the Bell et al. and Kay and Sevy models have similar psychometric properties including adequate temporal stability, internal consistency, and discriminant validity. The Kay model demonstrated somewhat better concurrent validity with cognitive test measures, while the Dollfus model demonstrated relatively poor psychometrics. The symptom composition of a narrowly defined cognitively disorganized subtype and a more broadly defined cognitively impaired subtype are discussed in terms of their value for schizophrenia research. (C) 1999 Elsevier Science B.V. All rights reserved.