title: Behavioral validation of avolition in schizophrenia.
abstract: BACKGROUND
  Since Kraepelin, avolition, a core symptom of schizophrenia, has been defined as a decrease in spontaneous, self-initiated and purposeful behaviors observed in daily life activities. However, the concurrent validity of commonly-used avolition measures has not been studied, and direct observation may offer a more objective way to measure avolition.
  
  
  METHODS
  A direct observation measure of spontaneous and self-initiated behaviors that can be observed in an inpatient setting was defined with the use of time sampling method. This direct observation measure was used with fifty inpatients with schizophrenia. Additionally, patients were asked to rate their current interest in and their level of engagement in 10 active behaviors during the preceding 7 days. Clinicians rated the patients' engagement in the same activities for the preceding 7 days as well.
  
  
  RESULTS
  The direct observation measure showed very good psychometric properties. Three clinical negative symptom scales showed moderate to high correlation with the direct measure. Concerning the retrospective ratings, patients' self-assessments were poorly correlated with clinicians' ratings, but showed high correlation with their subjective interests.
  
  
  CONCLUSIONS
  Clinical rating scales of negative symptoms show moderate to good concurrent validity as measures of avolition in schizophrenia. However, patients' self-reports do not appear to provide valid indices of avolition. Our results favor clinical negative symptoms scales that use observers' reports only, over patients' self-reports. The direct observation of patients' behavior offers a precise and objective measure of avolition that may be useful in drug challenges and clinical trials.
authors.affiliation: Nathan S. Kline Institute for Psychiatric Research, Orangeburg, NY, United States. Ftremeau@NKI.RFMH.ORG
authors.forename: Fabien
authors.initials: F
authors.lastname: Trémeau
authors.forename: Karen A
authors.initials: KA
authors.lastname: Nolan
authors.forename: Dolores
authors.initials: D
authors.lastname: Malaspina
authors.forename: Daniel C
authors.initials: DC
authors.lastname: Javitt
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007398:Interpersonal Relations; D008297:Male; D008875:Middle Aged; D009042:Motivation; D019370:Observation / Q000379:methods*; D011594:Psychometrics / Q000295:instrumentation; D015203:Reproducibility of Results; D012559:Schizophrenia / Q000503:physiopathology*; D012565:Schizophrenic Psychology; D012647:Self-Assessment