Im still not understanding what is the need/meaning/function for FEV1/FVC ratio measurement? What does that truly show? A Deeper obstruction? Do people with COPD only have the lower levels of FEV1/FVC? If there’s FEV1 then why do we need this ratio?
For instance:
my FVC is 113%
my FEV1 is 90 %
And my FEV1/FVC ratio is “66”
So, what number is giving off the “mild obstruction” diagnosis?