I can't find the post from earlier today about how the percentages are arrived at, but have just been assured by my practice nurse that in my case 70% result means 70% of average lung function for my gender, race, height and weight - nothing to do with smoking history as stated by a UK contributor - maybe hypercat? not sure ....
She did say it would be possible but not very accurate for very sophisticated sprirometry equipment to evaluate such information as length of time smoking, amount smoked and so on, but this probably wouldn't be totally accurate.
I'm very relieved, because if my 40 odd years of smoking had been taken into account, my 70% (stable since diagnosed 3 years ago) would've been 70% of hardly anything!
I only mentioned smoking history as an example of being diagnosed with copd. The rest is exactly what I said - you are 70% of the average for your height, weight and age etc. So if the average lung function is 90% for your group then you are 7O% of this like you said. This is exactly how I explained it in my reply to the poster.
Maybe, I cleaned out my emails and can't find it now, but however you expressed it I understood you to mean that the lung function percentage was arrived at AFTER taking years of smoking into account.
Damn these cataracts: I have to concentrate far too hard to read the screen and it makes me tired, so it's quite possible I misunderstood you. I'm glad I had it cleared up quickly with the practice nurse.
I'd already stopped smoking years before, but decades too late: I was always fit and healthy, hardly ever colds or flu or I probably would've stopped sooner.
Nowadays other's people's cigarette smoke, even a tiny bit, affects my lungs quite badly, sometimes into the next day and I'm glad I don't have to go into Melbourne very often because of the pollution