Reliability and validity of childhood asthma control test in a population of Chinese asthmatic children

Background No quick and easy assessment tool is presently available to measure asthma control and outcome in Chinese children. Methods We translated an established seven-item questionnaire into the Chinese Childhood Asthma Control Test (C-CACT) to measure asthma symptoms and their effect on daily function in 247 children aged 4-11 years enrolled from specialty clinics around Tainan. Subjects were classed as having either intermittent or persistent asthma and were evaluated at two outpatient visits 4-8 weeks apart (baseline and follow-up). Results C-CACT at baseline correlated significantly with physician evaluation scores (PES) except in predicted peak expiratory flow rate. There were significant differences for mean C-CACT score and mean PES between the intermittent group and persistent group. Internal consistency reliability of the survey was 0.741 at baseline and 0.759 at the follow-up visit. Test-retest reliability among 209 patients with the same specialist rating of asthma control at baseline and follow-up was r = 0.546 (P < 0.001). C-CACT scores of patients whose therapy needed to be stepped up was significantly lower than in those with unchanged or stepped-down therapy (F = 39.61, P < 0.001). Conclusions C-CACT provides a reliable, valid, and responsive measure of asthma control in Chinese children.