A Cardio Touch 3000S (BIONET, Korea) was used to measure vital lung capacity during pulmonary function examination.
The subjects were seated on a chair in an upright position during the examination to reduce compensation of the trunk
and improve safety. To measure vital lung capacity, forced vital capacity (FVC), forced expiratory volume in one second
(FEV1), FEV1/FVC, and peak expiratory flow (PEF) were measured three times and the highest values were used