A Case-control Study on the Differentiation Between Cough Variant Asthma and Chronic Cough

Inclusion Criteria: * (1) age from 18 years old to 65 years old; (2) clinical diagnosis of CVA and CC . Exclusion Criteria: * Exclusion criteria for CVA were: a history of COPD, bronchiectasis, bronchitis, cystic fibrosisor pneumonia, interstitial lung disease, pulmonary tuberculosis, lung cancer; cough caused by drugs or treatments; patients with upper airway cough syndromes (UACS) and gastroesophageal reflux-related cough (GERC) or other apparent causes of cough; patients who used corticosteroid (ICS) in the previous four weeks; Exclusion criteria for CC were: a history of variable airway limitation.