title: Case-finding for depressive and exhausted mood in the general population: reliability and validity of a symptom-driven diagnostic scale. Results from the prospective MONICA/KORA Augsburg Study.
abstract: OBJECTIVE
  Depressed and exhausted mood warrants epidemiological scrutiny as a cardiovascular risk factor. We evaluated the reliability and validity of a symptom-driven diagnostic scale.
  
  
  METHODS
  To assess a depressed mood, items were derived from an extended battery of psychosocial questionnaires in a population-based study including 11,949 subjects aged 25 to 74 years.
  
  
  RESULTS
  Eight items from the 24-item von Zerssen checklist were extracted by factor analysis resulting in an approximately normally distributed scale (range 0-24; mean=8.23, SD 4.76). Median for men was 8.00 and 10.00 for women. Its internal consistency was high (Cronbach's alpha 0.88). Test-retest reliability of a sub-sample was 0.83. Determining concurrent validity, correlation coefficients against a single depression questionnaire in 8237 subjects (p < 0.001) and SF-36 subscales (vitality and mental health) (both p < 0.0001) in 4226 subjects proved to be significant. Construct validity was confirmed by significant associations (all p < 0.001) with sleeping complaints, social isolation, and unhappiness. Test values for men above the 80th percentile exhibited significant hazard ratios for subsequent total mortality (80th percentile: HR 2.17, 95% CI: 1.31-13.55).
  
  
  CONCLUSIONS
  The scale comprises eight items describing motivational depletion, decreased vitality, irritability, and an anxious mood with sufficient internal and external reliability, concurrent and construct validity. Its normal distribution allows a graduated analysis of different thresholds. The instrument may be particularly useful to identify exhausted and depressed mood of otherwise apparently healthy subjects in the general population.
authors.affiliation: GSF National Research Center for Environment and Health, Institute of Epidemiology, Neuherberg, Germany. ladwig@gsf.de
authors.forename: Karl-Heinz
authors.initials: KH
authors.lastname: Ladwig
authors.forename: Birgitt
authors.initials: B
authors.lastname: Marten-Mittag
authors.forename: Jens
authors.initials: J
authors.lastname: Baumert
authors.forename: Hannelore
authors.initials: H
authors.lastname: Löwel
authors.forename: Angela
authors.initials: A
authors.lastname: Döring
mesh_terms: D000328:Adult; D017677:Age Distribution; D000368:Aged; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000523:psychology; D003430:Cross-Sectional Studies; D003863:Depression / Q000150:complications / Q000175:diagnosis* / Q000453:epidemiology; D020920:Dyssomnias; D005163:Factor Analysis, Statistical; D005221:Fatigue / Q000150:complications / Q000175:diagnosis* / Q000453:epidemiology; D005260:Female; D005858:Germany / Q000453:epidemiology; D006240:Happiness; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011569:Psychiatric Status Rating Scales; D011594:Psychometrics / Q000295:instrumentation*; D012307:Risk Factors; D012737:Sex Factors; D012934:Social Isolation; D012944:Social Support; D011795:Surveys and Questionnaires