title: Validation of a health-related quality of life instrument for primary ciliary dyskinesia (QOL-PCD).
abstract: Quality of life (QOL)-primary ciliary dyskinesia (PCD) is the first disease-specific, health-related QOL instrument for PCD. Psychometric validation of QOL-PCD assesses the performance of this measure in adults, including its reliability, validity and responsiveness to change.
  
  
  
  Seventy-two adults (mean (range) age: 33 years (18-79 years); mean (range) FEV1% predicted: 68 (26-115)) with PCD completed the 49-item QOL-PCD and generic QOL measures: Short-Form 36 Health Survey, Sino-Nasal Outcome Test 20 (SNOT-20) and St George Respiratory Questionnaire (SGRQ)-C. Thirty-five participants repeated QOL-PCD 10-14 days later to measure stability or reproducibility of the measure.
  
  
  
  Multitrait analysis was used to evaluate how the items loaded on 10 hypothesised scales: physical, emotional, role and social functioning, treatment burden, vitality, health perceptions, upper respiratory symptoms, lower respiratory symptoms and ears and hearing symptoms. This analysis of item-to-total correlations led to 9 items being dropped; the validated measure now comprises 40 items. Each scale had excellent internal consistency (Cronbach's α: 0.74 to 0.94). Two-week test-retest demonstrated stability for all scales (intraclass coefficients 0.73 to 0.96). Significant correlations were obtained between QOL-PCD scores and age and FEV1. Strong relationships were also found between QOL-PCD scales and similar constructs on generic questionnaires, for example, lower respiratory symptoms and SGRQ-C (r=0.72, p<0.001), while weak correlations were found between measures of different constructs.
  
  
  
  QOL-PCD has demonstrated good internal consistency, test-retest reliability, convergent and divergent validity. QOL-PCD offers a promising tool for evaluating new therapies and for measuring symptoms, functioning and QOL during routine care.
authors.affiliation: Primary Ciliary Dyskinesia Centre, University Hospital Southampton NHS Foundation Trust, Southampton, UK.|NIHR Southampton Respiratory Biomedical Research Unit, University of Southampton and University Hospital Southampton NHS Foundation Trust, Southampton, UK.|Academic Unit of Clinical and Experimental Sciences Faculty of Medicine, University of Southampton, Southampton, UK.|School of Applied Psychology, University College Cork, Cork, Ireland.
authors.forename: Laura
authors.initials: L
authors.lastname: Behan
authors.affiliation: Department of Pediatrics and Marsico Lung Institute, University of North Carolina School of Medicine, Chapel Hill, North Carolina, USA.
authors.forename: Margaret W
authors.initials: MW
authors.lastname: Leigh
authors.affiliation: Division of Respiratory Medicine, The Hospital for Sick Children, Toronto, Ontario, Canada.|Child Health Evaluative Sciences, The Hospital for Sick Children, Toronto, Ontario, Canada.|Department of Pediatrics, University of Toronto, Toronto, Ontario, Canada.|Institute of Health Policy, Management and Education, University of Toronto, Toronto, Ontario, Canada.
authors.forename: Sharon D
authors.initials: SD
authors.lastname: Dell
authors.affiliation: School of Applied Psychology, University College Cork, Cork, Ireland.
authors.forename: Audrey
authors.initials: A
authors.lastname: Dunn Galvin
authors.affiliation: Department of Psychology, University of Miami, Coral Gables, Florida, USA.
authors.forename: Alexandra L
authors.initials: AL
authors.lastname: Quittner
authors.affiliation: Primary Ciliary Dyskinesia Centre, University Hospital Southampton NHS Foundation Trust, Southampton, UK.|NIHR Southampton Respiratory Biomedical Research Unit, University of Southampton and University Hospital Southampton NHS Foundation Trust, Southampton, UK.|Academic Unit of Clinical and Experimental Sciences Faculty of Medicine, University of Southampton, Southampton, UK.
authors.forename: Jane S
authors.initials: JS
authors.lastname: Lucas
mesh_terms: D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000368:Aged; D004651:Employment / Q000706:statistics & numerical data; D005260:Female; D005541:Forced Expiratory Volume / Q000502:physiology; D006801:Humans; D007619:Kartagener Syndrome / Q000150:complications / Q000503:physiopathology / Q000523:psychology / Q000534:rehabilitation*; D008297:Male; D008875:Middle Aged; D011594:Psychometrics; D011788:Quality of Life; D015203:Reproducibility of Results; D012140:Respiratory Tract Diseases / Q000209:etiology; D017678:Sex Distribution; D011795:Surveys and Questionnaires; D055815:Young Adult
keywords: Psychology; Rare lung diseases; Respiratory Measurement