Table 1.

Study characteristics by case–control status

		Cases (n = 11,433)		Controls (n = 14,147)
		N	%	N	%
Age category	20- <40 years	109	1.0	199	1.4
	40- <50 years	934	8.2	1,287	9.1
	50- <60 years	3,040	26.6	3,597	25.4
	60- <70 years	4,657	40.7	5,809	41.1
	70- <80 years	2,616	22.9	3,210	22.7
	≥80 years	77	0.7	45	0.3
Age [years]	Median (interquartile range)	63 (56–69)		63 (56–69)
Smoking status	Non-smoker	279	2.4	3,506	24.8
	Former smoker	3,957	34.6	6,321	44.7
	Current smoker	7,051	61.7	3,950	27.9
	Other types of tobacco only	146	1.3	370	2.6
Cumulative tobacco consumption [pack-years] in former and current smokers	Median (interquartile range)	39 (27–53)		23 (11–38)
Educational level	<6 years	2,210	19.3	1,857	13.1
	6–9 years	5,689	49.8	5,994	42.4
	10–13 years	2,295	20.1	3,718	26.3
	University degree	1,239	10.8	2,578	18.2
List A occupation	Never	9,808	85.8	12,878	91.0
	Ever	1,625	14.2	1,269	9.0
Blue/White collar worker	Blue collar	6,284	55.0	5,828	41.2
	White collar	3,803	33.3	6,751	47.7
	Mixed blue/white collar	1,346	11.8	1,568	11.1
Last residence	Urban (≥10,000 inhabit.)	7,389	64.6	9,004	63.6
	Rural (<10,000 inhabit.)	1,816	15.9	1,849	13.1
	Missing	2,228	19.5	3,294	23.3
Time-weighted average occupational social prestige	High (>45- 78 points)	2,215	19.4	4,592	32.5
	Medium (>35- ≤45 points)	3,980	34.8	4,854	34.3
	Low (13- ≤35 points)	5,238	45.8	4,701	33.2
Histological lung cancer subtype	Squamous cell cancer	4,875	42.6
	Small cell lung cancer	1,843	16.1
	Adenocarcinoma	2,818	24.6
	Other or mixed	1,825	16.0
	Missing	72	0.6