Table 4—

Agreement between various definitions of chronic obstructive pulmonary disease(COPD)

	LLN of FEV₁/FVC ratio				Doctor-diagnosed COPD
	Post-bronchodilator		Pre-bronchodilator		Yes	No
	Yes	No	Yes	No	Yes	No
GOLD
Yes	125	136	120	141	18	243
No	0	747	59	688	18	729
κ coefficient	0.577 (0.5162–0.638)		0.424 (0.359–0.489)		0.06 (0.0169–0.107)
p-value	p<0.001^#		p<0.001^#		p = 0.001^#
LLN of FEV₁/FVC post-bronchdilator
Yes			88	37	8	117
No			91	792	28	855
κ coefficient			0.507 (0.434–0.580)		0.047 (-0.0157–0.110)
p-value			p<0.001^#		p = 0.069
LLN of FEV₁/FVC pre-bronchdilator
Yes					9	170
No					27	802
κ coefficient					0.026 (-0.023–0.075)
p-value					p = 0.247

Data are presented as n or κ coefficient (95% confidence interval), unless otherwise stated. LLN: lower limit of normal range; FEV₁: forced expiratory volume in one second; FVC: forced vital capacity; GOLD: Global Initiative for Chronic Obstructive Lung Disease. ^#: p<0.05.