Table 2.

Frequency of interlobar heterogeneity in GOLD stage III/IV patients

	Frequency of interlobar heterogeneity, %
	perceived as interlobar heterogeneitya	true interlobar heterogeneityb
Upper lobe
Left	53	40
Right	56	32
Both	42	26
Middle lobe/lingula
Left	47	35
Right	49	37
Both	31	19
Lower lobe
Left	16	4
Right	13	3
Both	7	1
At least one lobe of the lung
Left	78	57
Right	81	52
Both	65	39

HI = Heterogeneity index.

^aLobar HI ≥1.15 for the lobe of interest.

^bSegmental HI ≥1.15 for all segments in the lobe of interest.