Measuring asthma severity: instrument refinement.

The focus of this study is to evaluate a brief parent-report instrument, the Severity of Chronic Asthma (SCA) scale, that conforms to the national guidelines for assessing asthma. Convergent validity was found between the SCA and other measures related to asthma severity including an illness severity scale (How Bad is the Asthma?), asthma management scales for parents and children, and the pediatric quality-of-life scale. The SCA is a multidimensional scale with appropriate evidence of reliability and validity that may be a heuristic and effective measure in both clinical practice and research endeavors.