Utility of measuring FEV0.75/FVC ratio in preschoolers with uncontrolled wheezing disorder

Abstract

Uncontrolled wheezing disorder is common in preschoolers and disease control assessment is challenging as parents frequently overestimate the extent to which their child's disease is controlled. This is the first study of forced expiratory volume in t s (FEVt)/forced vital capacity (FVC) ratio measurements (i.e. FEV1/FVC, FEV0.75/FVC and FEV0.5/FVC) in wheezy preschoolers in relation to disease control. Our objective was to evaluate whether FEVt/FVC ratios less than the lower limit of normal (LLN; z-score <0.001). Only an FEV0.75/FVC ratio