Abstract
BACKGROUND: Exercise induced asthma (EIA) plays an important role in clinical evaluation. There has been little previous work validating EIA as reported directly by children and indirectly by their parents. AIMS: (1) To determine the strength of the association between children's symptoms of EIA and their physiological response to exercise in a laboratory setting. (2) To compare parents' perception of EIA with that of their children. (3) To seek factors influencing the perception of EIA. METHODS: Forty three asthmatic children and their parents answered a questionnaire, which included measures of symptom perception in EIA using visual analogue (VAS) and Likert scales. The children underwent a standardised treadmill exercise challenge, using spirometry to measure the physiological outcome, after which they and their parents independently completed the symptom scores. Twenty four subjects agreed to return for a second visit, in order to assess repeatability. RESULTS: The VAS and Likert scales were highly correlated. Children's symptom perception as measured by change in VAS scores related weakly to change in FEV(1) after exercise, and was unaffected by confounding factors such as age, gender, medication, and habitual exercise. Parents' perception of symptoms was unrelated to any physiological measure. There was no significant relation between parent and child VAS scores after exercise, and there was poor agreement between the Likert scale scores after exercise. The repeatability of the perception of change in FEV(1) after exercise was poor for both parents and children. CONCLUSION: Physicians should obtain reports of EIA from children rather than parents, but be aware of their limited accuracy and repeatability.