Bao W, et al. - Small-airway function tests were assessed as predictors of bronchial hyperresponsiveness (BHR) in adult patients with chronic cough. In patients with chronic cough and BHR, the presence of small-airway dysfunction was noted. As a negative predictive parameter for BHR, forced expiratory flow between 25% and 75% (FEF_25%-75%) displayed value, especially in combination with fractional exhaled nitric oxide (FENO). Additionally, a positive bronchial provocation test was strongly predicted by FENO > 43 ppb and FEF_25%-75% < 78.5%.