title: Method of assessment determines prevalence of suicidal ideation among patients with depression.
abstract: BACKGROUND
  How different ways of assessing suicidal ideation influence its prevalence, correlates and predictive validity among patients with major depressive disorder (MDD) remains unclear.
  
  
  METHODS
  Within the Vantaa Primary Care Depression Study (PC-VDS, 91 patients) and the Vantaa Depression Study (VDS, 153 psychiatric out-and 41 inpatients), suicidal ideation was assessed with the Scale for Suicidal Ideation (SSI), Hamilton Depression Scale (HAM-D) item 3 and Beck Depression Inventory (BDI) item 9, and by asking whether patients had seriously considered suicide during the episode. The positive and negative predictive values (PPV, NPV) for suicide attempts during a six-month follow-up were investigated.
  
  
  RESULTS
  Depending on the setting, 56-88% of patients had suicidal ideation in some of the assessments, but only 8-44% in all of them. Agreement ranged from negligible to moderate (kappa 0.06-0.64), being lowest among primary care patients. The correlates of suicidal ideation overlapped. No assessment had optimal sensitivity, specificity, PPV and NPV. Nevertheless, PPVs ranged up to 43%.
  
  
  CONCLUSIONS
  Which MDD patient is classified as having suicidal ideation depends strongly on the method of assessment, with the greatest variation likely in primary care. Differences in assessments may cause inconsistency in risk factors. Predicting suicide attempts is difficult, but not futile.
authors.affiliation: Department of Mental Health and Alcohol Research, National Institute for Health and Welfare, Helsinki, Finland; Department of Psychiatry, Helsinki University Central Hospital, P.O. Box 590, 00029 HUS.
authors.forename: M
authors.initials: M
authors.lastname: Vuorilehto
authors.affiliation: Department of Psychiatry, City of Helsinki, Health Centre, Psychiatry, Helsinki, Finland.
authors.forename: H M
authors.initials: HM
authors.lastname: Valtonen
authors.affiliation: Department of Mental Health and Alcohol Research, National Institute for Health and Welfare, Helsinki, Finland; Department of Psychiatry, Helsinki University Central Hospital, P.O. Box 590, 00029 HUS.
authors.forename: T
authors.initials: T
authors.lastname: Melartin
authors.affiliation: Department of Mental Health and Alcohol Research, National Institute for Health and Welfare, Helsinki, Finland.
authors.forename: P
authors.initials: P
authors.lastname: Sokero
authors.affiliation: Department of Psychiatry, City of Helsinki, Health Centre, Psychiatry, Helsinki, Finland.
authors.forename: K
authors.initials: K
authors.lastname: Suominen
authors.affiliation: Department of Mental Health and Alcohol Research, National Institute for Health and Welfare, Helsinki, Finland; Department of Psychiatry, Helsinki University Central Hospital, P.O. Box 590, 00029 HUS; Department of Psychiatry, University of Helsinki, Institute of Clinical Medicine, P.O. Box 22, FIN-00014, Finland. Electronic address: erkki.isometsa@hus.fi.
authors.forename: E T
authors.initials: ET
authors.lastname: Isometsä
mesh_terms: D000328:Adult; D015331:Cohort Studies; D003865:Major Depressive Disorder / Q000453:epidemiology* / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015995:Prevalence; D011569:Psychiatric Status Rating Scales; D012307:Risk Factors; D012680:Sensitivity and Specificity; D059020:Suicidal Ideation; D013405:Suicide / Q000523:psychology / Q000706:statistics & numerical data*
keywords: Major depressive disorder; Primary health care; Psychiatric care; Suicidal ideation; Suicide; Suicide attempts