Quantification of asthma control: validation of the Asthma Control Scoring System

Background:  We developed an instrument for quantifying asthma control, the Asthma Control Scoring System (ACSS), based on the criteria proposed by the Canadian Asthma Consensus Guidelines. Objective:  To assess the measurement properties of the ACSS. Methods:  The ACSS and two other questionnaires were completed by 44 asthmatic patients on a first visit and 2 weeks later. The ACSS evaluates three types of parameters: clinical, physiologic, and inflammatory. These parameters are each quantified to obtain a maximal score of 100% and a global score is calculated as the mean of these scores. Results:  The analysis showed sufficient internal consistency for every section of the ACSS (Cronbach's‐ α ranging from 0.72 to 0.88). Pearson's correlations indicated good test–retest reliability for the clinical score ( r  = 0.59, P  = 0.005), the physiologic score ( r  = 0.86, P  < 0.0001), the inflammatory score ( r  = 0.71, P  = 0.049), and the global score ( r  = 0.65, P  = 0.001). Cross‐sectional and longitudinal construct validity were supported by moderate correlations between the ACSS scores and corresponding instruments. Conclusions:  The ACSS is a valid tool for quantifying asthma control parameters, using a percent score. Further research should determine the usefulness of such an instrument as a means to improve asthma management and reduce related morbidity.