Definition | Reference |
Self-reported diagnosis of chronic bronchitis or emphysema “self report” | See text for description of variables used |
FEV1/FVC <0.70 and FEV1 <80% pred# | GOLD Stage IIA 12 |
FEV1/FVC < lower limit of normal¶ | See text for comparability to ATS guidelines 13 |
FEV1/FVC <88% pred in males and <89% pred in females “per cent predicted” | See text for comparability to ERS guidelines 14 |
FEV1/FVC <0.70 “fixed ratio” # | “Clinical” definition 6, equivalent to GOLD Stage I 12 |
FEV1: forced expiratory volume in one second
FVC: forced vital capacity
% pred: % predicted
GOLD: Global Initiative for Chronic Obstructive Lung Disease
ATS; American Thoracic Society
ERS: European Respiratory Society
#: GOLD specifies that all FEV1 values should refer topostbronchodilator FEV1. The third National Health and Nutrition Examination Survey (NHANES III) did not include reversibility testing 12
¶: the ATS specifies that spirometry should be performed pre- and postbronchodilator. NHANES III did not include reversibility testing 13