title: The COPD-SIB: a newly developed disease-specific item bank to measure health-related quality of life in patients with chronic obstructive pulmonary disease.
abstract: BACKGROUND
  Health-related quality of life (HRQoL) is widely used as an outcome measure in the evaluation of treatment interventions in patients with chronic obstructive pulmonary disease (COPD). In order to address challenges associated with existing fixed-length measures (e.g., too long to be used routinely, too short to ensure both content validity and reliability), a COPD-specific item bank (COPD-SIB) was developed.
  
  
  METHODS
  Items were selected based on literature review and interviews with Dutch COPD patients, with a strong focus on both content validity and item comprehension. The psychometric quality of the item bank was evaluated using Mokken Scale Analysis and parametric Item Response Theory, using data of 666 COPD patients.
  
  
  RESULTS
  The final item bank contains 46 items that form a strong scale, tapping into eight important themes that were identified based on literature review and patient interviews: Coping with disease/symptoms, adaptability; Autonomy; Anxiety about the course/end-state of the disease, hopelessness; Positive psychological functioning; Situations triggering or enhancing breathing problems; Symptoms; Activity; Impact.
  
  
  CONCLUSIONS
  The 46-item COPD-SIB has good psychometric properties and content validity. Items are available in Dutch and English. The COPD-SIB can be used as a stand-alone instrument, or to inform computerised adaptive testing.
authors.affiliation: Centre for Educational Measurement at the University of Oslo (CEMO), Faculty of Educational Sciences, University of Oslo, Oslo, Norway. m.c.s.paap@cemo.uio.no.|Department of Research Methodology, Measurement, and Data-Analysis, Behavioural, Management and Social Sciences, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands. m.c.s.paap@cemo.uio.no.
authors.forename: Muirne C S
authors.identifier: http://orcid.org/0000-0002-1173-7070
authors.initials: MC
authors.lastname: Paap
authors.affiliation: Department of Clinical Psychology, Behavioural and Social Sciences, University of Groningen, Groningen, The Netherlands.
authors.forename: Lonneke I M
authors.initials: LI
authors.lastname: Lenferink
authors.affiliation: University of Twente, Enschede, The Netherlands.
authors.forename: Nadine
authors.initials: N
authors.lastname: Herzog
authors.affiliation: Department of Research Methodology, Measurement, and Data-Analysis, Behavioural, Management and Social Sciences, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands.
authors.forename: Karel A
authors.initials: KA
authors.lastname: Kroeze
authors.affiliation: Department of Research Methodology, Measurement, and Data-Analysis, Behavioural, Management and Social Sciences, University of Twente, P.O. Box 217, 7500 AE, Enschede, The Netherlands.|Medical School Twente, Medisch Spectrum Twente, Enschede, The Netherlands.
authors.forename: Job
authors.initials: J
authors.lastname: van der Palen
mesh_terms: D000223:Adaptation, Psychological; D000328:Adult; D000368:Aged; D001007:Anxiety; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D017063:Outcome Assessment, Health Care / Q000379:methods* / Q000592:standards; D011594:Psychometrics / Q000379:methods / Q000592:standards; D029424:Pulmonary Disease, Chronic Obstructive / Q000523:psychology*; D011788:Quality of Life; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires
keywords: COPD; IRT; Item bank; Item response theory; MRF-26; Patient perspective; QoL-RIQ; SGRQ-C; VQ11