ΔsRAW correlated with changes of intrathoracic gas volume ( ΔITGV ) ( r=0.61 ; p < 0.001 ) , residual volume ( ΔRV ) ( r=0.60 ; p < 0.001 ) , ΔFVC ( r=0.44 ; p=0.001 ) , and ΔVAS ( r=0.73 ; p < 0.001 ) , while ΔFEV1 correlated only with ΔFVC ( r=0.34 ; p=0.008 ) .
intrathoracic gas volume, residual volume, ΔFVC, ΔVAS, ΔFEV1