The lung function tests were performed using a dry spirometer, Mijnhardt Vicatest 5 by following the ATS guidelines [ 17].
FEV1 and FVC were then measured using a dry bellows spirometer (Vitalograph, Buckingham, UK), taking the best of three technically satisfactory manoeuvres with the subject seated.
FVC, FEV1 and flow-volume curves were measured using a dry wedge spirometer (Chestac 11, Chest Co., Ltd., Tokyo, Japan).
FEV1 was calculated according to the best successive readings in 100 mL using a dry bellows spirometer (Vitalograph Ltd ,Maids Moreton, UK) [ 23, 24].
Lung function test was performed in accordance with the American Thoracic Society guidelines [ 23], following ECG registration, using a dry volume spirometer, the Vicatest 5 (Gebr. Mijnhardt B.V., Odijk, Netherlands).
The measurements were performed according to the methods suggested by the American Thoracic Society 53 using a dry vitalograph spirometer (Vitalograph Ltd. Buckingham, England).
Forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) were performed by wearing nose clips in the seated position using a dry wedge spirometer (Vitalograph, Buckingham, UK), and the best of three readings was recorded.
Spirometry was conducted in accordance with the American Thoracic Society/European Respiratory Society guidelines (Miller et al. 2005) using a dry-rolling seal spirometer (Occupational Marketing, Inc., Houston, TX), and all tests were read by one investigator (Hankinson et al. 2010).
Dry the area using a dry towel.
