Determination of bronchodilator response cutoffs for oscillometry and consistency with spirometry

Bronchodilator response (BDR) for spirometry is defined as ≥200 mL and ≥12% improvement in FEV1. Previous studies advocated the BDR cutoffs for oscillometry based on healthy subjects. However, its application to asthma patients is not validated yet. This retrospective study aimed to determine the BDR cutoffs for oscillometry in asthma patients and assessed the consistency with spirometry.