Table 1.

Database information.

Number of cases	865 (5 excluded from 865)
Dates of acquisition	1997–1999 (8)
	2000–2004 (161)
	2005–2009 (192)
	2010–2014 (128)
	2015–2017 (326)
	NA (50)
Sex at birth	Male (384) female (431) NA (50)
Smoking status	Current (257) former (469) never (89) NA (50)
Age	Mean (66.8) SD (11.4) range (33–93)
Pack-years of smoking	Mean (36.2) SD (30.8) range (0–199)
Scanner manufacturer	GE medical systems siemens
Exposure time	Range (250–2100)
kVp	(100, 120, 140)
Slice thickness	Range (0.5–10 mm)
Emphysema severity	None (508) mild/moderate (240) severe (117)
Dominant emphysema phenotype	Centrilobular (284) paraseptal (33) panlobular (40)