The structure of symptom report in asthma - A reevaluation

Objectives: We studied the structure of symptom report in a sample of Briti sh asthma patients using the Asthma Symptom Checklist (ASC). Methods: The A SC was administered to 193 patients, together with a questionnaire on demog raphics and asthma-related information and the Perceived Control of Asthma Questionnaire. Results: Principal Component Analysis yielded evidence for a six-dimensional structure of the ASC, with positively correlated subscales for panic-fear, irritation, obstruction-dyspnea, obstruction-congestion, f atigue, and hyperventilation symptoms. Individual subscales showed good to excellent item characteristics and internal consistencies in individual sub scales. Panic-fear and obstruction-congestion were related to self-reported duration of oral corticosteroid intake. Other ASC subscales were positivel y related to aspects of health care utilization, limitations in daily activ ity, and lower perceived control of asthma mainly in women. The dyspnea sub scale of the ASC showed only little relationship with either of these varia bles. Conclusion: The ASC can reliably assess the multidimensional structur e of asthma symptom report. Its subscales are associated with important asp ects of asthma management behavior. (C) 2001 Elsevier Science Inc. All righ ts reserved.