Pediatric asthma quality of life questionnaire (PAQLQ): Validation among asthmatic children in Thailand

Quality of life (QoL) is an important consideration among asthma sufferers. The Pediatric Asthma Quality of Life Questionnaire (PAQLQ) is one of the most widely used instruments for measuring health-related QoL in children with asthma. The standardized version of PAQLQ contains 23 questions in three domains, i.e., activity limitation, symptoms and emotional function. The objective of this study was to validate the Thai-translated version of the PAQLQ. The study design consisted of a five-week single cohort study. Patients recorded symptoms, and peak expiratory flow rate (PEFR) each morning and evening during the first and fifth week of the study in asthma diary. At each clinic visit, a trained-interviewer administered the PAQLQ and performed spirometric measurements. Fifty-one children, ages between 7 and 17 yr participated in the study. Scores from the asthma diary were used to classify patients into stable vs. unstable groups. The construct validity of the questionnaire was confirmed in both cross-sectional and longitudinal studies by demonstrating correlations between various PAQLQ domains with clinical asthma parameters (asthma diary, beta-agonist use and PEFR). There was high internal consistency for scores of the three domains (Cronbach's alpha-coefficient = 0.83-0.95). For those with stable asthma, the reliability of PAQLQ was good for the rating scale (intra-class correlation coefficient--ICC = 0.84) and for total score (alpha = 0.97) indicating high reproducibility of the PAQLQ. The significant difference of changes QoL scores between stable and unstable groups was observed in all domains. We conclude that the Thai version of PAQLQ is valid and reliable for implementing in Thai children with asthma.