title: Content comparison of health-related quality of life instruments for obstructive sleep apnea.
abstract: OBJECTIVE
  Due to the increasing importance of quality of life assessments in obstructive sleep apnea (OSA) patients and due to an increased use of the International Classification of Functioning, Disability and Health (ICF), for comparative purposes it is essential to understand the relationship between health-related quality of life (HRQOL) instruments and the ICF. The purpose of this study was to compare the content covered by OSA-specific instruments using the ICF.
  
  
  METHODS
  OSA-specific instruments were identified, including the Calgary Sleep Apnea Quality of Life Index, the Functional Outcomes of Sleep Questionnaire, the Obstructive Sleep Apnea Patient-Oriented Severity Index, and the Quebec Sleep Questionnaire, and linked to the ICF by six health professionals according to standardized guidelines. The degree of agreement between health professionals was calculated by means of the kappa statistic.
  
  
  RESULTS
  A total of 308 concepts were identified and linked to 78 different ICF categories; 35 categories of the component body function, one category of the component body structure, 38 categories of the component activities and participation, and four categories of the component environmental factors. Only contents within the chapters mental functions, mobility and social life were addressed by all instruments. Forty-seven categories were covered by only one instrument.
  
  
  CONCLUSIONS
  The ICF proved highly useful for the comparison of HRQOL instruments. This analysis may help researchers and clinicians to choose the most appropriate HRQOL instrument for a specific purpose as well as help to compare study outcomes of studies using different instruments for HRQOL assessment.
authors.affiliation: Department of Internal Medicine, University Hospital Bern, Bern, Switzerland. armin.stucki@insel.ch
authors.forename: Armin
authors.initials: A
authors.lastname: Stucki
authors.forename: Alarcos
authors.initials: A
authors.lastname: Cieza
authors.forename: Macé M
authors.initials: MM
authors.lastname: Schuurmans
authors.forename: Bedirhan
authors.initials: B
authors.lastname: Ustun
authors.forename: Gerold
authors.initials: G
authors.lastname: Stucki
authors.forename: Felix
authors.initials: F
authors.lastname: Gradinger
authors.forename: Markku
authors.initials: M
authors.lastname: Partinen
mesh_terms: D006970:Disorders of Excessive Somnolence / Q000453:epidemiology*; D006304:Health Status; D006801:Humans; D008403:Mass Screening; D011788:Quality of Life / Q000523:psychology*; D020181:Sleep Apnea, Obstructive / Q000453:epidemiology*; D011795:Surveys and Questionnaires