title: Relation between duration and severity in bereavement-related depression.
abstract: OBJECTIVE
  Prolonged duration is commonly used as an indicator that bereavement-related depression (BRD) is pathological. DSM-IV replaced the traditional 1-year pathology cut-point by a 2-month cut-point. Yet, little evidence exists regarding the validity of these cut-points in indicating increased BRD severity. This study evaluated the validity of the 2-month and 1-year cut-points in differentiating less severe from more severe BRDs in a nationally representative U.S. sample.
  
  
  METHODS
  National Comorbidity Survey respondents with BRD's (n = 152) lasting 0-8, 9-52 and >52 weeks were evaluated for depression severity using six severity indicators. Cut-point validity was established by discontinuities in severity levels between durations below and above the cut-point.
  
  
  RESULTS
  Bereavement-related depressions of >52-week duration were significantly higher than 9- to 52-week BRDs on four of six severity indicators and on a cumulative overall severity measure of mean number of severity indicators per person, whereas ≤8-week and 9- to 52-week durational categories differed on one severity indicator and not on overall severity. Additional analyses using durations 0-12, 13-26, 27-52 and >52 weeks suggested that alternative <52-week cut-points also lack validity.
  
  
  CONCLUSIONS
  The traditional 1-year cut-point validly identifies increasing BRD severity; DSM's 2-month cut-point does not. Duration does not indicate increasing BRD severity before 1 year. Research using the 2-month cut-point may yield misleading results.
authors.affiliation: Silver School of Social Work, New York University, NY 10003, USA. wakefield@nyu.edu
authors.forename: J C
authors.initials: JC
authors.lastname: Wakefield
authors.forename: M F
authors.initials: MF
authors.lastname: Schmitz
authors.forename: J C
authors.initials: JC
authors.lastname: Baer
mesh_terms: D000328:Adult; D001601:Bereavement; D003863:Depression / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology* / Q000523:psychology; D003865:Major Depressive Disorder / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology* / Q000523:psychology; D003937:Diagnosis, Differential; D039721:Diagnostic and Statistical Manual of Mental Disorders; D005260:Female; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D012959:Socioeconomic Factors; D013997:Time Factors; D014481:United States / Q000453:epidemiology