Structure of Negative Symptoms in Schizophrenia
Results from a WIPH Centre for Psychiatry and Mental Health study investigating competing theoretical models to determine which best describes the factorial structure of negative symptoms in schizophrenia do not support recent data on the superiority of the five-factor model defined by the NMIH-MATRICS consensus. Negative symptoms are predominant features of schizophrenia, but there is a long-standing debate about the nature of their inner composition. Identification of their structure is crucial to provide a better treatment. Increasing evidence has supported the superiority of a five-factor model (alogia, blunted affect, anhedonia, avolition, and asociality as defined by the NMIH-MATRICS Consensus), however, previous data primarily used the Brief Negative Symptoms Scale. In this study, exploratory factor analysis was used to investigate the structure of negative symptoms based on the Clinical Assessment Interview for Negative Symptoms (CAINS). In a cross-validation sample, confirmatory analysis tested four competing theoretical (one-factor, two-factor, five-factor, and hierarchical factor) models, and two exploratory factor analysis-derived models. Corresponding author, Manuela Russo, said that the results suggest that a CAINS-rated model from exploratory factor analysis consisting of five factors (expression, motivation for recreational activities, social activities, vocational, and close/intimate relationships) was an excellent fit to the data, but further research is needed.