title: Validation of a new questionnaire with generic and disease-specific qualities: the McGill COPD Quality of Life Questionnaire.
abstract: BACKGROUND
  A validated health-related quality of life questionnaire in chronic obstructive pulmonary disease (COPD) with advantages of both generic- and disease-specific questionnaires is needed to capture patients' perspectives of severity and impact of the disease. The McGill COPD questionnaire was created to include these advantages in English and French. It assesses three domains: symptoms, physical function and feelings with 29 items (12 from the 36-item Short-Form Health Survey with 17 from the previously developed COPD-specific module).
  
  
  OBJECTIVE
  To evaluate the psychometric properties of this newly developed hybrid questionnaire in subjects with COPD.
  
  
  METHODS
  Data from a multicentre, prospective cohort study involving four hospitals with COPD subjects undergoing pulmonary rehabilitation were used. Patient evaluations included health-related quality of life (the new McGill COPD questionnaire, the St Georges Respiratory Questionnaire and the 36-item Short-Form Health Survey) and pulmonary function tests pre-and postrehabilitation. Reliability, validity and responsiveness were tested.
  
  
  RESULTS
  The study included 246 COPD subjects (111 females) with a mean age of 66 years, 87% ex- and 8% current smokers (mean 61 pack-years) and mean forced expiratory volume in 1 s of 1.12 L (Global initiative for chronic Obstructive Lung Disease stages: 2, 27%; 3, 33%; and 4, 37%). Missing data were <2% and floor and ceiling effects were <5%. Internal consistency (Cronbach's alpha) was 0.68 to 0.82. Test-retest reliability (intracorrelation coefficients) ranged from 0.74 to 0.96 for the subscales, and 0.95 for the total score. Correlation with the St George's Respiratory Questionnaire was moderately high (r=-0.88 [95% CI -0.91 to -0.84]), consistent with the a priori hypothesis for convergent validity. The effect size was 0.33 (pre-postrehabilitation mean score difference = 6), suggesting a small to moderate change.
  
  
  CONCLUSIONS
  The new McGill COPD questionnaire showed high internal consistency, test-retest reliability, validity and moderate responsiveness in COPD subjects.
authors.affiliation: University of Ottawa, The Ottawa Hospital, The Otta Hospital Research Institute, Ottawa, Ontario.
authors.forename: Smita
authors.initials: S
authors.lastname: Pakhale
authors.forename: Sharon
authors.initials: S
authors.lastname: Wood-Dauphinee
authors.forename: Adriana
authors.initials: A
authors.lastname: Spahija
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Collet
authors.forename: Francois
authors.initials: F
authors.lastname: Maltais
authors.forename: Sarah
authors.initials: S
authors.lastname: Bernard
authors.forename: Marc
authors.initials: M
authors.lastname: Baltzan
authors.forename: Michel
authors.initials: M
authors.lastname: Rouleau
authors.forename: Jean
authors.initials: J
authors.lastname: Bourbeau
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002170:Canada; D015331:Cohort Studies; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D011594:Psychometrics; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications* / Q000175:diagnosis / Q000523:psychology*; D011788:Quality of Life; D015203:Reproducibility of Results; D012129:Respiratory Function Tests; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires