title: From items to syndromes in the Hypomania Checklist (HCL-32): psychometric validation and clinical validity analysis.
abstract: BACKGROUND
  The Hypomania Checklist (HCL-32) was developed to identify subthreshold bipolarity in patients with major depression. An HCL-32 version with fewer items has been suggested.
  
  
  METHODS
  Principal component analysis (PCA) without rotation was used to identify active/elevated mood versus risk-taking/irritable behaviour in the HCL-32. Using the Bech-Rafaelsen Mania Scale as index of clinical validity a shorter version was developed. Item response theory analysis was used to evaluate whether the total score of the HCL-32 was sufficient to measure subthreshold bipolarity. The short 13-item Mood Disorder Questionnaire (MDQ) was used for comparison.
  
  
  RESULTS
  In accordance with the SCID-II criteria, we included 59 bipolar I and 63 unipolar (depressed) outpatients who had recently been discharged from inpatient treatment. In the HCL-32, PCA identified the two contrasting factors: active/elevated mood versus risk-taking/irritable behaviour. The clinical validation analysis focussed on 20 HCL items as the most acceptable (HCL-20). Item response analysis accepted that the total scores of the HCL-32/HCL-20 were a sufficient statistic, as was the total score of the MDQ. Among the unipolar (depressed) patients not responding to their antidepressive medication, subtreshold bipolarity was identified in 55% of patients using the HCL-20, 36% using the HCL-32, but only 18% using the MDQ.
  
  
  CONCLUSIONS
  Only outpatients recently discharged from inpatient treatment were studied. A further limitation is that 9.5% of the unipolar patients had only suffered from one episode, which, however had led to hospitalisation.
  
  
  CONCLUSIONS
  The HCL-20 was found to identify subthreshold bipolarity in up to 55% of inpatients with major depressive disorder not responding to antidepressive medication.
authors.affiliation: Psychiatric Research Unit, Frederiksborg General Hospital, Copenhagen University, Hillerød, Denmark. Per.bech@regionh.dk
authors.forename: P
authors.initials: P
authors.lastname: Bech
authors.forename: E M
authors.initials: EM
authors.lastname: Christensen
authors.forename: M
authors.initials: M
authors.lastname: Vinberg
authors.forename: G
authors.initials: G
authors.lastname: Bech-Andersen
authors.forename: L V
authors.initials: LV
authors.lastname: Kessing
mesh_terms: D000328:Adult; D001714:Bipolar Disorder / Q000175:diagnosis* / Q000523:psychology*; D057189:Checklist / Q000706:statistics & numerical data*; D003718:Denmark; D003865:Major Depressive Disorder / Q000175:diagnosis* / Q000523:psychology*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011594:Psychometrics / Q000706:statistics & numerical data; D012008:Recurrence; D015203:Reproducibility of Results; D013577:Syndrome