title: Assessing depression related severity and functional impairment: the Overall Depression Severity and Impairment Scale (ODSIS).
abstract: BACKGROUND
  The Overall Depression Severity and Impairment Scale (ODSIS) is a brief, five-item measure for assessing the frequency and intensity of depressive symptoms, as well as functional impairments in pleasurable activities, work or school, and interpersonal relationships due to depression. Although this scale is expected to be useful in various psychiatric and mental health settings, the reliability, validity, and interpretability have not yet been fully examined. This study was designed to examine the reliability, factorial, convergent, and discriminant validity of a Japanese version of the ODSIS, as well as its ability to distinguish between individuals with and without a major depressive disorder diagnosis.
  
  
  METHODS
  From a pool of registrants at an internet survey company, 2830 non-clinical and clinical participants were selected randomly (619 with major depressive disorder, 619 with panic disorder, 576 with social anxiety disorder, 645 with obsessive-compulsive disorder, and 371 non-clinical panelists). Participants were asked to respond to the ODSIS and conventional measures of depression, functional impairment, anxiety, neuroticism, satisfaction with life, and emotion regulation.
  
  
  RESULTS
  Exploratory and confirmatory factor analysis of three split subsamples indicated the unidimensional factor structure of ODSIS. Multi-group confirmatory factor analysis showed invariance of factor loadings between non-clinical and clinical subsamples. The ODSIS also showed excellent internal consistency and test-retest intraclass correlation coefficients. Convergence and discriminance of the ODSIS with various measures were in line with our expectations. Receiver operating characteristic curve analyses showed that the ODSIS was able to detect a major depressive syndrome accurately.
  
  
  CONCLUSIONS
  This study supports the reliability and validity of ODSIS in a non-western population, which can be interpreted as demonstrating cross-cultural validity.
authors: National Center for Cognitive Behavior Therapy and Research, National Center of Neurology and Psychiatry, Kodaira, Japan.
authors: Masaya
authors: M
authors: Ito
authors: Boston University, Boston, Massachusetts, United States of America.
authors: Kate H
authors: KH
authors: Bentley
authors: National Institute of Mental Health, National Center of Neurology and Psychiatry, Kodaira, Japan.
authors: Yuki
authors: Y
authors: Oe
authors: Tokyo Medical University, Tokyo, Japan.
authors: Shun
authors: S
authors: Nakajima
authors: University of Tsukuba, Tsukuba, Japan.
authors: Hiroko
authors: H
authors: Fujisato
authors: National Center for Cognitive Behavior Therapy and Research, National Center of Neurology and Psychiatry, Kodaira, Japan.
authors: Noriko
authors: N
authors: Kato
authors: National Center for Cognitive Behavior Therapy and Research, National Center of Neurology and Psychiatry, Kodaira, Japan; University of Tsukuba, Tsukuba, Japan.
authors: Mitsuhiro
authors: M
authors: Miyamae
authors: National Center of Neurology and Psychiatry, Kodaira, Japan.
authors: Ayako
authors: A
authors: Kanie
authors: National Center for Cognitive Behavior Therapy and Research, National Center of Neurology and Psychiatry, Kodaira, Japan.
authors: Masaru
authors: M
authors: Horikoshi
authors: Boston University, Boston, Massachusetts, United States of America.
authors: David H
authors: DH
authors: Barlow
mesh_terms: D000328:Adult; D001007:Anxiety / Q000175:diagnosis* / Q000453:epidemiology / Q000473:pathology; D003863:Depression / Q000175:diagnosis* / Q000453:epidemiology / Q000473:pathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009771:Obsessive-Compulsive Disorder / Q000175:diagnosis* / Q000453:epidemiology / Q000473:pathology; D016584:Panic Disorder / Q000175:diagnosis* / Q000453:epidemiology / Q000473:pathology; D011569:Psychiatric Status Rating Scales; D011594:Psychometrics; D012720:Severity of Illness Index