Table 2.

Discriminant validity tests on mean ACT scores at baseline visits (n=117)

^*This stratification of percentage of predicted FEV₁ values was roughly based on the FEV₁ values mentioned in the four steps of asthma severity in the GINA guidelines (2); ^†This stratification method of AQLQ scores was done simply by dividing the 5-scale point scores into 4 groups. Although this stratification method has not been validated, it was based on the fact that change in score of 0.5 in 7-point scale represents minimal important change of quality of life (22) and that score difference of 1 which is twice the score of minimal important change mentioned above would stratify groups differing in quality of life.

FEV₁, forced expiratory volume in one second; AQLQ, asthma quality of life questionnaire.