Objective: To provide additional validity data for the Asthma Control TestTM (ACT) using a different criterion measure, setting, and population.
Study design: Cross-sectional survey.
Methods: Questionnaires were completed at home by a random sample of 570 members of a large integrated healthcare organization who were 35 years or older with utilization suggestive of active asthma. The questionnaires included the ACT; another validated asthma control questionnaire (Asthma Therapy Assessment Questionnaire [ATAQ]), which was used as the criterion measure; a validated quality-of-life tool (Mini Asthma Quality of Life Questionnaire [Mini-AQLQ]); a validated symptom frequency scale (Asthma Outcomes Monitoring System); and information regarding demographics.
Results: The ACT score was statistically significantly correlated with findings on the ATAQ (P = -0.73), Mini-AQLQ (P = 0.77), and symptom frequency scale (P = -0.69). The optimal ACT cutoff for well-controlled asthma (ATAQ level, 0) was confirmed to be 20 or higher (sensitivity, 78.1%; specificity, 83.8%), and the optimal ACT cutoff for poorly controlled asthma (ATAQ level, 3-4) was confirmed to be 15 or lower (sensitivity, 90.4%; specificity, 80.9%).
Conclusion: These data further support the validity of the ACT in the home setting among a random sample of patients with asthma.