%0 Journal Article %A Jane Kirkby %A Raffaella Nenna %A Aisling McGowan %T Changes in FEV1 over time in COPD and the importance of spirometry reference ranges: the devil is in the detail %D 2019 %R 10.1183/20734735.0252-2019 %J Breathe %P 337-339 %V 15 %N 4 %U https://breathe.ersjournals.com/content/breathe/15/4/337.full.pdf