Validity of the PANSS cognitive factor as a measurement of cognitive performance in schizophrenia

Abstract

IntroductionThe Positive and Negative Syndrome Scale (PANSS) is a widely used instrument for measuring symptomatology in patients with schizophrenia. Numerous studies have analyzed the factorial structure of this scale and have suggested a five factor model, namely: negative, positive, excited, anxiety/depression, and disorganized (or cognitive). The latter factor has been related to neuropsychological tests, with a view to analyzing its utility as a measure of cognitive functioning in schizophrenia, but data are inconclusive. The aim of the present study was to analyze the factorial structure of the PANSS and to assess the relationships between factors and neurocognitive tests. Material and methodsThe sample comprised 235 outpatients diagnosed with schizophrenia. To investigate the factorial structure of the PANSS, a principal component factor analysis was performed. Cognitive functioning was measured with a shortened version of the Barcelona Test. ResultsUnlike previous studies, our study obtained a six-factor model, with disorganized and cognitive symptoms separated in two different factors. The cognitive factor obtained in this study was related to all subtests of the Barcelona Test. The disorganized factor, however, was only related to two of these subtests. ConclusionsOur results support the use of a six-factor model and suggest that the cognitive factor could be a valid measure of cognitive deficits in schizophrenia, although the use of a standard neuropsychological battery is advisable.