The Asthma Impact Record (AIR) index: a rating scale to evaluate the quality of life of asthmatic patients in France.

Asthma is a chronic disease, which affects patients' daily lives. The goal of this study was the development of a disease-specific scale to evaluate quality of life in asthmatic patients in France: The Asthma Impact Record Index (AIR Index). The study was conducted with the participation of 486 asthmatic patients using the following steps: 1) selection of dichotomous items; 2) reduction of the number of items; 3) study of reproducibility of the questionnaire; 4) weighting of items; 5) study of the reliability and validity of the final version of the AIR Index. The final version of the AIR Index contains 63 unweighted items. The items were classified into subscales representing the main dimensions of quality of life: 1) physical, which was itself split into two subscales: a) physical activities; and b) symptoms; 2) psychological; and 3) social or relational. The internal consistency, measured by Cronbach's alpha coefficients, was found to be high, for the global scale and all subscales (range 0.79-0.94). The concurrent validity, evaluated by studying the relationship between the score values on the global scale and the subscales, and the parameters reflecting disease severity, was also high. We conclude that the AIR Index might represent a useful evaluative and discriminant instrument in studying quality of life in asthma in French populations.