<prompt> In COPD which is true -FEV1FVC0.7FEVlFVCRVTLV  <response>: Ans. is a i.e., FEV1 FVC 0.7 The lung function tests in obstructive lung disease can be summarized as -o Forced expiratory vital capacity FEVc - Normal to slightly decreasedo Forced expiratory volume in 1 sec FEV1-Decrease out of proportion to FVCo FEV1FEV1-Decrease can be as low as 20 - 30o Peak expiratory flow rate-Decreasedo Total lung capacity-Increaseo Residual volume-Increaseso Functional residual capacity-Higher 