P166 External validation of the minimal clinically important difference of fractional exhaled nitric oxide using the asthma control questionnaire: a secondary analysis of two RCTs in mild or moderate asthma

Abstract

IntroductionThe utility of fractional exhaled nitric oxide (FeNO) in randomised controlled trials (RCTs) of asthma, particularly the minimal clinical important difference (MCID), is uncertain. The American Thoracic Society recommends that...