Table 1. Distribution of known risk factors for stomach cancer in cases and controls.

	Total 645 (n)	%	Cases 165 (n)	%	Controls 480 (n)	%	p-value
Gender
Male	328	50.8	84	50.9	244	50.8
Female	317	49.2	81	49.1	236	49.2	0.987
Age at interview or cancer diagnosis
< = 35	49	7.6	21	12.7	28	5.8
>35–50	118	18.3	27	16.4	91	19.0
>50–65	238	36.9	64	38.8	174	36.2
>65	240	37.2	53	32.1	187	39.0	0.020
Interview method
Phone	176	27.3	44	26.7	132	27.5
Face	433	67.1	119	72.1	314	65.4
Post	36	5.6	2	1.2	34	7.1	0.015
Deprivation quintile (Q)
Q1 (least)	66	10.2	8	4.9	58	12.1
Q2	89	13.8	11	6.7	78	16.2
Q3	101	15.7	22	13.3	79	16.5
Q4	167	25.9	38	23.0	129	26.9
Q5 (most)	222	34.4	86	52.1	136	28.3	<0.0001
Smoking status
Non-smoker	199	30.8	35	21.2	164	34.2
Ex-smoker	301	46.7	93	56.4	208	43.3
Current smoker	145	22.5	37	22.4	108	22.5	0.004
Exposure to ETS* as an adult
Yes	489	75.8	147	89.1	342	71.3
No	156	24.2	18	10.9	138	28.7	<0.0001
Childhood people to room ratio**
< = 1.0	189	29.3	34	20.6	155	32.3
>1.0–2.0	294	45.6	72	43.6	222	46.3
>2.0	156	24.2	56	34.0	100	20.8	0.0006
Missing	6	0.9	3	1.8	3	0.6
Parent with stomach cancer
Yes	49	7.6	29	17.6	164	4.1
No	553	85.7	126	76.3	208	89.0	<0.0001
Missing	43	6.7	10	6.1	108	6.9
BMI (kg/m2)
<25	185	28.7	69	41.8	116	24.2
25–30	215	33.3	59	35.8	156	32.5
>30	232	36.0	37	22.4	195	40.6	<0.0001
Missing	13	2.0	0	0.0	13	2.7
In the past year, how many times/week did you exercise?
None	165	25.6	42	25.4	123	25.6
1–2	118	18.3	20	12.1	98	20.4
3–4	135	20.9	41	24.9	94	19.6
5+ / week	227	35.2	62	37.6	165	34.4	0.086
In the past year, how many servings /week did you eat vegetables?
<7	127	19.7	22	13.3	105	21.9
7–21	362	56.1	86	52.1	276	57.5
> = 21 / week	156	24.2	57	34.6	99	20.6	0.0005
In the past year, how many servings/week did you eat fruits?
<7	215	33.3	42	25.5	173	36.1
7–14	182	28.2	49	29.7	133	27.7
> = 14 / week	248	38.5	74	44.8	174	36.2	0.036
In the past year, how many times/week did you eat red meat?
None	45	7.0	16	9.7	29	6.0
1–2	179	27.8	45	27.3	134	27.9
3–4	284	44.0	71	43.0	213	44.4
5+ / week	137	21.2	33	20.0	104	21.7	0.461
In the past year, how many times/week did you eat white meat?
None	33	5.1	11	6.7	22	4.6
1–2	344	53.3	73	44.2	271	56.5
3–4	236	36.6	75	45.5	161	33.5
5+ / week	32	5.0	6	3.6	26	5.4	0.018
In the past year, how many times/week did you eat fish?
None	161	25.0	31	18.8	130	27.1
1–2	390	60.4	93	56.4	297	61.9
3–4	76	11.8	33	20.0	43	8.9
5+ / week	18	2.8	8	4.8	10	2.1	0.0002
In the past year, how many times /week did you eat dried or salty food?
None	304	47.1	56	34.0	248	51.7
1–2	280	43.4	82	49.7	198	41.2
3–4	41	6.4	21	12.7	20	4.2
5+ / week	20	3.1	6	3.6	14	2.9	<0.0001
In the past year, how often did you have a drink containing alcohol?
Never	208	32.2	70	42.4	138	28.7
Monthly or less	164	25.4	58	35.1	106	22.1
2–4 times/month	99	15.4	16	9.7	83	17.3
2–3 times/ week	82	12.7	10	6.1	72	15.0
4 + times /week	92	14.3	11	6.7	81	16.9	<0.0001
Ever diagnosed with diabetes
Yes	136	21.1	46	27.9	90	18.8
No	509	78.9	119	72.1	390	81.2	0.013
Ever tested for H pylori
Yes	44	6.8	30	18.2	14	2.9
No	514	79.7	75	45.4	439	91.5	<0.0001
Don't know	87	13.5	60	36.4	27	5.6
Ever diagnosed with dyspepsia
Yes	115	17.8	47	28.5	68	14.2
No	517	80.2	110	66.7	407	84.8	<0.0001
Don't know	13	2.0	8	4.8	5	1.0

* Environmental tobacco smoke

** Number of people living in house divided by number of rooms