title: Measuring depression with a well-being index: further evidence for the validity of the WHO Well-Being Index (WHO-5) as a measure of the severity of depression.
abstract: BACKGROUND
  In recent years, the WHO Wellbeing Index (WHO-5) has been used as a screening measure for depression. Nevertheless, research on the validity of this measure in the context of clinical depression is sparse.
  
  
  OBJECTIVE
  The aim of the present study was to investigate the measurement invariance of the WHO-5 across depressed and non-depressed individuals, as well as the shape and specificity of its relationship to measures of depression severity.
  
  
  METHODS
  Of the 414 subjects who completed the WHO-5 and the Beck Depression Inventory-II (BDI-II), 207 had a diagnosis of a major depressive episode (MDE). A subsample also completed the Beck Anxiety Inventory (BAI) and was assessed by clinicians using the Hamilton Depression Rating Scale (HAM-D) and the Hamilton Anxiety Rating Scale (HAM-A).
  
  
  RESULTS
  The WHO-5 demonstrated strong measurement invariance regarding the presence or absence of a current MDE. The WHO-5 showed a very high negative association with self- and observer-rated measures of depressive symptoms, especially in the range of mild to moderate symptoms. These associations were still substantial after controlling for measures of anxiety symptoms.
  
  
  CONCLUSIONS
  In addition to a diagnostic interview, only one measure for self- and observer-rated symptoms of depression was used. Furthermore, the observer-rated measure was only assessed in one subsample that exhibited a somewhat restricted range of depression severity.
  
  
  CONCLUSIONS
  Although this index was originally designed as a measure of well-being, the results support the use of the WHO-5 in the context of depression research.
authors.affiliation: Department of Psychology, University of Zurich, Switzerland. Electronic address: tobias.krieger@psychologie.uzh.ch.
authors.forename: Tobias
authors.initials: T
authors.lastname: Krieger
authors.affiliation: Department of Psychology, University of Kassel, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Zimmermann
authors.affiliation: Research Group Longitudinal and Intervention Research, Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, Mannheim, Medical Faculty Mannheim, University of Heidelberg, Germany.
authors.forename: Silke
authors.initials: S
authors.lastname: Huffziger
authors.affiliation: Department of Cognitive and Clinical Neuroscience, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.
authors.forename: Bettina
authors.initials: B
authors.lastname: Ubl
authors.affiliation: Department of Cognitive and Clinical Neuroscience, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.
authors.forename: Carsten
authors.initials: C
authors.lastname: Diener
authors.affiliation: Research Group Longitudinal and Intervention Research, Department of Psychiatry and Psychotherapy, Central Institute of Mental Health, Mannheim, Medical Faculty Mannheim, University of Heidelberg, Germany.
authors.forename: Christine
authors.initials: C
authors.lastname: Kuehner
authors.affiliation: Department of Psychology, University of Zurich, Switzerland.
authors.forename: Martin
authors.initials: M
authors.lastname: Grosse Holtforth
mesh_terms: D000293:Adolescent; D000328:Adult; D003865:Major Depressive Disorder / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008297:Male; D008403:Mass Screening; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D014944:World Health Organization; D055815:Young Adult
keywords: BDI-II; Depression severity; Measurement invariance; WHO-5; Well-being