FEV1/FVC ratio of >0.65: Most IPF studies have inclusion of >0.70. Why are we going with 0.65? Might get some emphysema patients with 0.65 (though there is an exclusion criteria for emphysema).

Bear in mind this is not a typical IPF study as we are focused on one of the key symptoms (cough) rather than disease progression. We recognise that a ratio of 0.65 may result in some emphysema slipping through, but provided it is not dominant and they have also have clearly established IPF and are coughing then this is not a particular concern.