Component structure of the Positive And Negative Syndrome Scale (PANSS) in patients with recent-onset schizophrenia and spectrum disorders

Rationale: Earlier studies have examined the symptom dimensions of the PANSS (Positive And Negative Syndrome Scale) in patients with chronic schizophrenia. Results have suggested that three to eight component solutions best explain underlying symptom dimensions. Objectives: To examine the component structure of the PANSS and the MADRS (Montgomery Asberg Depression Rating Scale) in young patients with recent-onset schizophrenia and related disorders and the correlations between the components of both instruments. Methods: Symptomatology was measured in 138 patients with recent-onset schizophrenia, by administering the PANSS and the MADRS. Results: Principal component analysis of the PANSS revealed five components: a positive, negative, depression, agitation-excitement and disorganisation component. The MADRS only showed one component. A high correlation was found between the depression component of the PANSS and the overall score of the MADRS (rho=0.87, P<0.001). A moderate correlation was found between the PANSS negative component and the overall score of the MADRS (rho=0.51, P<0.001). Conclusions: The data suggest a five component structure of the PANSS. The depression component of the PANSS seems to be a valid way of assessing depression in patients with recent-onset schizophrenia.