Childhood Asthma Control Test and spirometry values in school-age children.

Objective: To determine the relationship between child and parent reports of asthma control using the Childhood Asthma Control Test (C-ACT) and spirometry.

Methods: This descriptive study included 648 children ages 5-11 years from a school-based asthma program. Not well-controlled asthma was defined as forced expiratory volume in 1 s (FEV1) and by FEV1/forced vital capacity (FVC) of 80% predicted or lower. Sensitivity and specificity of C-ACT scores for low FEV1 and FEV1/FVC levels were calculated. Logistic regression was used to obtain the area under the receiver operating characteristic curve (AUC) for C-ACT score categories by FEV1 level.

Results: Mean child age was 8.2 years, mean C-ACT score was 20.3 ( = 3.96), mean FEV1 was 94.3% ( = 17.1), and mean FEV1/FVC was 81.3 ( = 8.5). Children with an FEV1 of 80% or less had significantly lower C-ACT scores than those with an FEV1 > 80% ( = .023,  = -2.015,  = 167); 95% CI [. -1.79 to -0.018]). The sensitivity and specificity of a C-ACT score of 19 or less for an FEV1 of 80% predicted or lower were 44.9 and 66.4%. With a C-ACT score of 22 or less, sensitivity and specificity for low FEV1 were 67.7 and 30.9%. The AUC for a C-ACT score of 19 or less and FEV1 of 80% or lower was .444 while the AUC was higher at .507 for a CACT score of 22 or less.

Conclusion: The C-ACT is a useful screen but spirometry should be performed in children with persistent symptoms to assess current asthma control.