TABLEĀ 4

Severity of airway obstruction according to different staging systems

GOLD [2]ATS/ERS [24]Quanjer [25]
SubjectsSubjects at stage with respiratory symptomsSubjectsSubjects at stage with respiratory symptomsSubjectsSubjects at stage with respiratory symptoms
Subjects n1854576576
Mild1045 (56)283 (27)292 (51)98 (34)307 (53)104 (34)
Moderate704 (38)352 (50)125 (22)70 (56)90 (16)53 (59)
Moderately severeNANA73 (13)47 (64)90 (16)59 (66)
Severe90 (4.9)76 (85)59 (10)48 (81)69 (12)54 (78)
Very severe15 (1)13 (87)27 (5)26 (96)20 (3)19 (95)

Data are presented as n (%), unless otherwise stated. GOLD: Global Initiative for Chronic Obstructive Pulmonary Disease; ATS: American Thoracic Society; ERS: European Respiratory Society; NA: not applicable.