Reliability and Validity of the Malay Version Chronic Respiratory Questionnaire for used among COPD Patients

ABSTRACT

Introduction: Chronic Respiratory Questionnaire (CRQ) is one of the disease-specific questionnaires to assess health related quality of life (HRQoL) among chronic obstructive pulmonary disease (COPD) patients. Objectives: This study investigate the validity and reliability of Malay version CRQ among COPD patients. Methods: The CRQ was administered twice to 46 patients with COPD (mean FEV1 44% predicted, FEV1/ IVC 37% predicted) from Medical Center of University Kebangsaan Malaysia (PPUKM).Test-retest reliability was assessed using intra-class correlation coefficients (ICC). Internal consistency was determined using Crohnbach’s alpha coefficients (α = 0.7). Spearman’s correlation coefficient was done among the scores of CRQ, St George Respiratory Questionnaire (SGRQ) and sixminute walking test (6MWT) to examine the concurrent validity of the CRQ (p 0.70) was observed for 3 domains of CRQ with exception of dyspnoea domain (α = -0.631). Test retest reliability demonstrated strong correlation (ICC >0.80). Concurrent validity of CRQ, showed significant correlations observed between domain of SGRQ’s symptom, impact and total scores of SGRQ with CRQ’s dyspnoea and emotional function (-0.3< r < -0.4; p<0.05). Significant correlation was observed between 6MWT and CRQ’s fatigue domain (r= 0.390; p=0.007). Conclusions: The Malay version of CRQ is a reliable instrument for measuring health status of patients among chronic respiratory disease especially COPD. Items of fatigue, emotion, and mastery domain of the CRQ are reliable and valid and can be used to assess quality of life in patients with severe airways obstruction. Items of the dyspnoea dimension are less reliable and should not be included in the overall score of the CRQ in comparative research.