title: Comparison of scoring methods for the Brief Insomnia Questionnaire in a general population sample.
abstract: OBJECTIVE
  The Brief Insomnia Questionnaire (BIQ) is a lay-administered, structured interview to derive insomnia disorders according to the Diagnostic and Statistical Manual, Fourth Edition, Text Revision (DSM-IV-TR), International Classification of Diseases, Tenth Edition (ICD-10) and research diagnostic criteria/International Classification of Sleep Disorders, Second Edition (RDC/ICSD-2). The concordance between diagnoses derived from the BIQ and clinical interviews was only moderate and the prevalence estimates based on the BIQ were significantly different from estimates based on clinical interviews. We hypothesized that a modification of the scoring algorithm closer to the diagnostic criteria would improve the performance of the BIQ.
  
  
  METHODS
  Probability subsample of population-based epidemiological survey respondents (n=2011) completed clinical reappraisal (n=176) interviews. We compared the modified scoring with the original scoring in sensitivity, specificity, positive and negative predictive values, areas under the characteristic curve, and Cohen's kappa to detect DSM-IV-TR, ICD-10 and RDC/ICSD-2 insomnia diagnoses by the BIQ against clinical interviews.
  
  
  RESULTS
  The diagnostic accuracy was improved with the modified scoring. The areas under the receiver operating characteristic curve for the DSM-IV-TR, ICD-10, RDC/ICSD-2 and any of the insomnia diagnoses ranged from 0.76 to 0.87. Using the modified scoring, there was no significant difference between prevalence estimates based on the BIQ classification and clinical interviews.
  
  
  CONCLUSIONS
  The BIQ with modified scoring enhanced case detection and produced more accurate prevalence estimates of DSM-IV-TR, ICD-10 and RDC/ICSD-2 insomnia disorders. With scoring algorithms now extended to DSM-5 and ICSD-3 diagnoses, the BIQ should be more widely used in clinical and research settings.
authors.affiliation: Department of Psychiatry, University of Hong Kong, Hong Kong, China. Electronic address: kfchung@hkucc.hku.hk.
authors.forename: Ka-Fai
authors.initials: KF
authors.lastname: Chung
authors.affiliation: School of Chinese Medicine, University of Hong Kong, Hong Kong, China.
authors.forename: Wing-Fai
authors.initials: WF
authors.lastname: Yeung
authors.affiliation: Department of Psychology, University of Hong Kong, Hong Kong, China.
authors.forename: Fiona Yan-Yee
authors.initials: FY
authors.lastname: Ho
authors.affiliation: School of Public Health, University of Hong Kong, Hong Kong, China.
authors.forename: Lai-Ming
authors.initials: LM
authors.lastname: Ho
authors.affiliation: Department of Psychology, Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Kam-Ping
authors.initials: KP
authors.lastname: Yung
authors.affiliation: Department of Psychiatry, University of Hong Kong, Hong Kong, China.
authors.forename: Yee-Man
authors.initials: YM
authors.lastname: Yu
authors.affiliation: Department of Psychiatry, University of Hong Kong, Hong Kong, China.
authors.forename: Chi-Wa
authors.initials: CW
authors.lastname: Kwok
mesh_terms: D039721:Diagnostic and Statistical Manual of Mental Disorders; D006801:Humans; D038801:International Classification of Diseases; D015995:Prevalence; D012494:Sampling Studies; D012720:Severity of Illness Index; D007319:Sleep Initiation and Maintenance Disorders / Q000175:diagnosis* / Q000453:epidemiology*; D011795:Surveys and Questionnaires / Q000592:standards / Q000706:statistics & numerical data
keywords: DSM-5; DSM-IV-TR; Diagnosis; ICD-10; ICSD-2; ICSD-3; Insomnia