title: The negative syndrome of schizophrenia: three -underlying components are better than two.
abstract: OBJECTIVE
  To analyse the underlying structure of the negative syndrome of schizophrenia as it is represented in the Brief Negative Symptom Scale.
  
  
  METHODS
  Cross-sectional, multicentre study, employing data from 190 evaluations.
  
  
  METHODS
  Exploratory factor analysis using the principal component analysis method.
  
  
  RESULTS
  The three-component solution explained 77.4% of the total variance. Pearson correlation coefficients between components were: 1-2=-0.494, 1-3=-0.117, and 2-3=0.179.
  
  
  CONCLUSIONS
  Our solution favours a three-component structure of the negative syndrome, consisting of: external world (anhedonia and asociality), inner world (avolition and blunted affect), and alogia, with the latter only marginally related to the two former components.
authors.affiliation: Department of Psychiatry, University of Oviedo, Spain; Centro de Investigación Biomédica en Red, Área de Salud Mental (CIBERSAM), Spain. Electronic address: albert@uniovi.es.
authors.forename: Maria Paz
authors.initials: MP
authors.lastname: Garcia-Portilla
authors.affiliation: Centro de Investigación Biomédica en Red, Área de Salud Mental (CIBERSAM), Spain.
authors.forename: Leticia
authors.initials: L
authors.lastname: Garcia-Alvarez
authors.affiliation: Centro de Investigación Biomédica en Red, Área de Salud Mental (CIBERSAM), Spain; Institut de Neuropsiquiatria i Adiccions, Parc de Salut Mar, Barcelona, Spain; Fundació IMIM, Barcelona, Spain.
authors.forename: Anna
authors.initials: A
authors.lastname: Mané
authors.affiliation: Centro de Investigación Biomédica en Red, Área de Salud Mental (CIBERSAM), Spain; Barcelona Clinic Schizophrenia Unit, Neuroscience Institute, Hospital Clinic of Barcelona, Spain.
authors.forename: Clemente
authors.initials: C
authors.lastname: Garcia-Rizo
authors.affiliation: Child and Adolescent Psychiatric Unit, Neuroscience Institute, Hospital Clinic of Barcelona, Spain; Institut d'Investigacions Biomediques August Pi i Sunyer (IDIBAPS), Barcelona, Spain.
authors.forename: Gisela
authors.initials: G
authors.lastname: Sugranyes
authors.affiliation: Institut de Neuropsiquiatria i Adiccions, Parc de Salut Mar, Barcelona, Spain; Fundació IMIM, Barcelona, Spain.
authors.forename: Daniel
authors.initials: D
authors.lastname: Bergé
authors.affiliation: Centro de Investigación Biomédica en Red, Área de Salud Mental (CIBERSAM), Spain; Barcelona Clinic Schizophrenia Unit, Neuroscience Institute, Hospital Clinic of Barcelona, Spain; Institut d'Investigacions Biomediques August Pi i Sunyer (IDIBAPS), Barcelona, Spain; Department of Psychiatry and Clinical Psychobiology, University of Barcelona, Barcelona, Spain.
authors.forename: Miguel
authors.initials: M
authors.lastname: Bernardo
authors.affiliation: Centro de Investigación Biomédica en Red, Área de Salud Mental (CIBERSAM), Spain; Department of Psychiatry, Behavioural and Clinical Neuroscience Institute, University of Cambridge, United Kingdom; Cambridgeshire and Peterborough NHS Foundation Trust, United Kingdom.
authors.forename: Emilio
authors.initials: E
authors.lastname: Fernández-Egea
authors.affiliation: Department of Psychiatry, University of Oviedo, Spain; Centro de Investigación Biomédica en Red, Área de Salud Mental (CIBERSAM), Spain.
authors.forename: Julio
authors.initials: J
authors.lastname: Bobes
mesh_terms: D000328:Adult; D000339:Affect; D059445:Anhedonia; D001037:Aphasia / Q000175:diagnosis; D003430:Cross-Sectional Studies; D005163:Factor Analysis, Statistical; D005260:Female; D006801:Humans; D008297:Male; D057181:Pleasure; D025341:Principal Component Analysis; D011569:Psychiatric Status Rating Scales; D012559:Schizophrenia / Q000175:diagnosis*; D012565:Schizophrenic Psychology; D012919:Social Behavior
keywords: BNSS; Negative syndrome; Principal component analysis