title: Examination of the Positive and Negative Syndrome Scale factor structure and longitudinal relationships with functioning in early psychosis.
abstract: OBJECTIVE
  We examined the factor structure of the Positive and Negative Syndrome Scale (PANSS) in early-episode psychosis and its relationships with functioning at baseline and follow-up.
  
  
  METHODS
  A total of 240 consecutive admissions to an early intervention in psychosis clinic were assessed at intake to the program with the PANSS, Global Assessment of Functioning (GAF) and Social and Occupational Functioning Assessment Scale (SOFAS). Seventy individuals were reassessed at follow-up. A maximum likelihood factor analysis was conducted on baseline PANSS scores and the ability of each factor to predict baseline and follow-up GAF and SOFAS was examined.
  
  
  RESULTS
  A five-factor model with varimax rotation was the best fit to our data and was largely congruent with factors found previously. The negative symptom factor was the best predictor of GAF and SOFAS at baseline and follow-up.
  
  
  CONCLUSIONS
  Negative symptoms are the best symptomatic predictor of functioning in individuals with early psychosis and are an important treatment target to improve recovery.
authors.affiliation: Department of Psychology, Queen's University, Kingston, Ontario, Canada.
authors.forename: Michael W
authors.initials: MW
authors.lastname: Best
authors.affiliation: Department of Psychology, Queen's University, Kingston, Ontario, Canada.
authors.forename: Michael
authors.initials: M
authors.lastname: Grossman
authors.affiliation: Department of Psychiatry, Queen's University, Kingston, Ontario, Canada.|Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada.
authors.forename: L Kola
authors.initials: LK
authors.lastname: Oyewumi
authors.affiliation: Department of Psychology, Queen's University, Kingston, Ontario, Canada.|Department of Psychiatry, Queen's University, Kingston, Ontario, Canada.|Centre for Neuroscience Studies, Queen's University, Kingston, Ontario, Canada.
authors.forename: Christopher R
authors.initials: CR
authors.lastname: Bowie
mesh_terms: D000293:Adolescent; D000328:Adult; D042241:Early Diagnosis; D005163:Factor Analysis, Statistical; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011569:Psychiatric Status Rating Scales; D011618:Psychotic Disorders / Q000175:diagnosis*; D055815:Young Adult
keywords: early psychosis intervention; factor analysis; psychotic disorder; schizophrenia; symptom