- A diagnosis of obstructive lung disease (with reference to the - International Primary Care Respiratory Group (IPCRG) Guidelines)(4). This being evidenced as a post bronchodilator ratio of FEV1/FVC < 0.7 at Visit 1 or 2 The patient has a post bronchodilator FEV1 of greater than 40% and less than 80% at Visit 1 or 2