The Knowledge, Attitude, and Self-Efficacy Asthma Questionnaire (KASE-AQ) is a paper-and-pencil instrument that was developed to allow physicians, behavioral scientists, and other health care personnel to assess asthma patients' knowledge regarding asthma, their attitudes about their asthma (including their willingness to cooperate with the physician in managing asthma), and their self-efficacy regarding their perceived ability to control the disorder. The KASE-AQ assesses changes in these patient variables following a particular intervention. The KASE-AQ proved to be reliable and internally consistent, and a factor analysis revealed presence of three subscales in the questionnaire (knowledge, attitude, and self-efficacy about asthma). Following asthma education and self-management training, experimental group subjects showed significant improvements in knowledge, attitude, and self-efficacy. Waiting-list control subjects showed similar improvements following training. Both groups' scores at 3-month follow-up remained significantly higher than their baseline scores on all 3 variables.