TY - JOUR T1 - Changes in FEV<sub>1</sub> over time in COPD and the importance of spirometry reference ranges: the devil is in the detail JF - Breathe JO - Breathe SP - 337 LP - 339 DO - 10.1183/20734735.0252-2019 VL - 15 IS - 4 AU - Jane Kirkby AU - Raffaella Nenna AU - Aisling McGowan Y1 - 2019/12/01 UR - http://breathe.ersjournals.com/content/15/4/337.abstract N2 - Spirometry plays a pivotal role in the diagnosis and management of COPD and other respiratory diseases. Since lung function varies with age, height, sex and ethnicity, accurate interpretation is dependent upon using appropriate reference ranges. In this article, we will present two landmark papers: one on changes in forced expiratory volume in 1 s (FEV1) over time in COPD [1] and the other focussing on spirometry reference ranges produced by the Global Lung Function Initiative (GLI) [2].A discussion of two landmark papers highlighting the use of spirometry as a sensitive measure of the rate of decline in FEV1 in COPD, and the importance of using the Global Lung Function Initiative reference data http://bit.ly/2C0Nhqa ER -