Toward a simplified measure of asthma severity for applied research.

There is no universally accepted and validated measure of asthma severity. For community research, clinical tests are too costly, and epidemiological assessments provide inadequate data on severity. Symptom measures may offer a practical alternative. This study assessed psychometric properties of symptom ratings of 91 asthmatic children. Reliability and validity of scales created from these items were examined. A sum scale of symptom ratings was internally consistent, reliable across time, and associated with concurrent health indices. This scale may be a practical measure of severity for use in community-based research.