Exploration of the Factor Structure of Positive and Negative Syndrome Scale in Schizophrenia Spectrum Disorders

The main Aim of the present research was to identify the factor structure of Postive and negative syndrome scale in schizophrenia spectrum disorders. One hundred fifty patients diagnosed with schizophrenia spectrum disorders (84 schizophrenics, 66 schizoaffective) in Fatemi and Eisar hospitals in Ardabil were selected by available sampling method and were asked to answer the Positive and negative syndrome scale (PANSS). The raw data were analyzed by factor analysis, and discriminate analysis statistical tests. In schizophrenia group, factor analysis of PANSS showed six factors, which included high tension, Poor rapport, delusion, Blunted affect, Conceptual disorganization and avolition, in the schizoaffective group six factors were identified namely: Blunted affect, distractibility, disintegration, high tension, Excitation and delusion. Result of discriminate analysis showed that 47.1% of disorders were correctly classified by PANSS. The results suggest that exploratory factor structure of positive and negative symptoms scale (PANSS) in the two groups of patients with schizophrenia disorders and schizoaffective disorder are different. Therefore, this instrument has acceptable construct validity in the diagnosis and clinical research.