title: Validity and Reliability of the Chronic Respiratory Disease Questionnaire in Elderly Individuals with Mild to Moderate Non-Cystic Fibrosis Bronchiectasis.
abstract: BACKGROUND
  The chronic respiratory disease questionnaire (CRDQ) is designed to assess health-related quality of life (HRQOL) in chronic respiratory conditions, but its reliability, validity and responsiveness in individuals with mild to moderate non-cystic fibrosis (CF) bronchiectasis are unclear.
  
  
  OBJECTIVE
  This study aimed to determine measurement properties of the CRDQ in non-CF bronchiectasis.
  
  
  METHODS
  Participants with non-CF bronchiectasis involved in a randomised controlled trial of exercise training were recruited. Internal consistency was assessed using Cronbach's α. Over 8 weeks, reliability was evaluated using intra-class correlation coefficients and Bland-Altman analysis for measures of agreement. Convergent and divergent validity was assessed by correlations with the other HRQOL questionnaires and the Hospital Anxiety and Depression Scale (HADS). The responsiveness to exercise training was assessed using effect sizes and standardised response means.
  
  
  RESULTS
  Eighty-five participants were included (mean age ± SD, 64 ± 13 years). Internal consistency was adequate (>0.7) for all CRDQ domains and the total score. Test-retest reliability ranged from 0.69 to 0.85 for each CRDQ domain and was 0.82 for the total score. Dyspnoea (CRDQ) was related to St George's respiratory questionnaire (SGRQ) symptoms only (r = 0.38), with no relationship to the Leicester cough questionnaire (LCQ) or HADS. Moderate correlations were found between the total score of the CRDQ, the SGRQ (rs = -0.49) and the LCQ score (rs = 0.51). Lower CRDQ scores were associated with higher anxiety and depression (rs = -0.46 to -0.56). The responsiveness of the CRDQ was small (effect size 0.1-0.24).
  
  
  CONCLUSIONS
  The CRDQ is a valid and reliable measure of HRQOL in mild to moderate non-CF bronchiectasis, but responsiveness was limited.
authors.affiliation: Physiotherapy, Western Health, Footscray, Vic., Australia.
authors.forename: Domagoj A
authors.initials: DA
authors.lastname: Vodanovich
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Bicknell
authors.forename: Anne E
authors.initials: AE
authors.lastname: Holland
authors.forename: Catherine J
authors.initials: CJ
authors.lastname: Hill
authors.forename: Nola
authors.initials: N
authors.lastname: Cecins
authors.forename: Sue
authors.initials: S
authors.lastname: Jenkins
authors.forename: Christine F
authors.initials: CF
authors.lastname: McDonald
authors.forename: Angela T
authors.initials: AT
authors.lastname: Burge
authors.forename: Philip
authors.initials: P
authors.lastname: Thompson
authors.forename: Robert G
authors.initials: RG
authors.lastname: Stirling
authors.forename: Annemarie L
authors.initials: AL
authors.lastname: Lee
mesh_terms: D000368:Aged; D001987:Bronchiectasis / Q000175:diagnosis / Q000209:etiology; D003371:Cough / Q000209:etiology; D005081:Exercise Therapy / Q000379:methods*; D017079:Exercise Tolerance; D005260:Female; D054624:Health Status Disparities; D006801:Humans; D008297:Male; D008875:Middle Aged; D011658:Pulmonary Fibrosis / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology / Q000523:psychology / Q000628:therapy; D011788:Quality of Life; D015203:Reproducibility of Results; D012129:Respiratory Function Tests; D012131:Respiratory Insufficiency / Q000175:diagnosis / Q000209:etiology; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires