Long-term consistency of an asthma questionnaire

Abstract

Objectives: To study the long-term consistency in answers to questions on chronic respiratory symptoms of a standardised questionnaire and in the diagnosis of asthma established on the basis of the answers to these questions* M ethods: A comparison of data collected by means of a test and a retest after a one-year interval. Population: 246 subjects aged 16 to 23. Main outcome measure: Cohen's kappa as measure of agreement between the answers to the first and the second ques tionnaire. Results: Cohen's kappa values of the questions on symptoms ranged between 0.22 and 0.62 and was 0.50 for the asthma diagnosis. O f the 20% of the study group who had asthma on the basis of the first ques tionnaire, 32% did not report of one single asthma symptom in the second one. Conclusions: In young adults aged 16 to 23, the long term consistency in answers to questions on respirat ory symptoms in a self-administered questionnaire and in the diagnosis of asthma assessed on the basis of the answers to these questions is unsatisfactory.