Statistical analysis
Results were expressed as median and interquartile range(IQR) or
proportions as required. While normality tests were negative, the
comparison of continuous variables(PACT, ACT, PAQLQ, FeNO, FEV1, FVC,
FEV1/FVC, FEF25%-75%) were performed using
Mann-Whitney U test. The percentages of these variables were compared
using qhi-square test. Correlation between tests were investigated by
Spearman correlation test. The diagnostic value of the PACT, ACT and
PAQLQ to detect “well controlled” asthma as defined by GINA was
determined by calculation of area under the curve(AUC) of receiver
operating characteristic(ROC) curves. The compatibility of the tests
with GINA criteria were assessed by kappa test(κ). Statistical
significance was defined if p<0.05. Analyses were performed
using SPSS statistical software, version 20.0(SPSS Inc, Chicago,
Illinois).