Aims: To develop an instrument for the measurement of, and to determine the level of, practical knowledge of self-management of acute asthma. Methods: Eighty patients with moderate/severe asthma attending a hospital-based asthma clinic responded to an interviewer-administered questionnaire. Subjects were asked to describe the action they would take in response to each of two hypothetical evolving attacks: (1) one of gradually increasing severity and (2) the other developing rapidly. Responses were scored according to the appropriateness of actions taken relevant to the stage of the attack. Transcripts of the responses were scored independently by three of the investigators according to a system based on Thoracic Society of Australia and New Zealand (TSANZ) and British Thoracic Society (BTS) consensus statements on asthma management. A 25-point scale was used on which 0 represented a total lack of appropriate responses and a score of 25 was an optimal response. Results: Interrater and intrarater reliability were excellent. Mean (+/-SD) scores for the slow and rapid onset attacks were 12.8+/-4.0 and 13.9+/-4.8, respectively. The scores for the two scenarios were predicted by each other (p=0.002) and by the interviewer's rating of asthma management knowledge (p=0.0004, p=0.0001), but not by age, sex, race, previous asthma morbidity, depression, or anxiety. In both scenarios, most patients indicated that they would increase inhaled p-agonist (85% for slow-onset scenarios and 94% for rapid-onset scenarios, respectively) and use their action plan and/or seek urgent medical advice at an appropriate time (74% and 70%). Although some would measure peak expiratory now (PEF) initially (54% and 30%), only a minority would continue to monitor PEF in the context of worsening acute asthma (30% and 24%). When a severe life-threatening situation was described, only 50% and 64%, respectively, indicated that they would call emergency services. Conclusions: Scenarios describing hypothetical asthma attacks are a useful and reproducible method of assessing practical knowledge of self-management of acute asthma. Patients presented with scenarios frequently made errors in their hypothetical responses. The errors made with scenarios, which parallel errors reported in real clinical situations, occurred despite the fact that this patient population had received considerable education and training about how to manage asthma. Most indicated they would not monitor PEF even in an exacerbation of asthma and would not call emergency services despite life-threatening asthma. These scenarios may allow us to explore the gap between knowledge about treatment and actual practice, and perhaps to help close that gap and thus reduce asthma morbidity and mortality.
