. Author manuscript; available in PMC: 2014 Mar 1.

Published in final edited form as: Cancer Causes Control. 2013 Jan 12;24(3):439–450. doi: 10.1007/s10552-012-0130-8

Table 1.

General characteristics of cases and controls

	Case		Control		Case		Control
	N	%	N	%	N	%	N	%

	Female				Male
Age (years)
<44	42	21.3	68	29.3	17	8.4	15	6.4
45–54	57	28.9	71	30.6	39	19.3	68	29.1
55–64	57	28.9	54	23.3	54	26.7	62	26.5
≥65	41	20.8	39	16.8	92	45.5	89	38.0
Total	197		232		202		234
	χ²=4.99, P=0.1729				χ²=6.27, P=0.0991
Education
Illiteracy	33	16.8	18	7.8	10	5.0	5	2.1
Primary school	60	30.5	41	17. 7	46	22.8	40	17.1
Middle school	57	28.9	84	36.2	67	33.2	91	38.9
High school	29	14.7	69	29.7	39	19.3	51	21.8
College & above	18	9.1	20	8.6	40	19.8	47	20.1
Total	197		232		202		234
	χ²=26.91, P<0.0001				χ²=5.58, P=0.2332
Annual personal income (RMB)
<1000	60	30.5	53	22.8	44	21.8	53	22.7
1000–2500	115	58.4	114	49.1	121	59.9	83	35.5
2500–5000	14	7.1	42	18.1	23	11.4	74	31.6
≥5000	8	4.1	23	9.9	14	6.9	24	10.3
Total	197		232		202		234
	χ²=18.97, P=0.0003				χ²=35.20, P<0.0001