Table 2.

Characteristics of head and neck cancer cases and controls

	Cases				Controls
	Total	No ever marijuana smokers 1	% ever marijuana smokers	Total	No ever marijuana smokers1	% ever marijuana smokers
Total	4029	408	10.1	5015	744	14.8
Study
Seattle	407	68	16.7	607	103	17.0
Tampa	207	5	2.4	897	4	0.4
Los Angeles	416	244	58.7	1002	543	54.2
Houston	829	49	5.9	865	64	7.4
Latin America
Buenos Aires	334	0	0.0	188	5	2.7
Havana	196	1	0.5	176	2	1.1
Goiania	391	7	1.8	242	4	1.7
Pelotas	128	1	0.8	225	0	0.0
Porto Alegre	191	2	1.0	152	1	0.7
Rio de Janeiro	428	12	2.8	241	7	2.9
Sao Paulo	502	19	3.8	420	11	2.6
Age Categories
<40	162	39	24.1	347	90	25.9
40–<45	281	53	18.9	455	131	28.8
45–<50	526	115	21.9	643	156	24.3
50–<55	690	95	13.8	945	208	22.0
55–<60	805	92	11.4	992	136	13.7
>=60	1565	14	0.9	1633	23	1.4
Sex
Women	785	66	8.4	1547	213	13.8
Men	3244	342	10.5	3468	531	15.3
Race
White non Hispanic	1526	280	18.3	2684	558	20.8
Black	145	52	35.9	271	71	26.2
Hispanic	141	27	19.1	328	68	20.7
Asian + other	47	10	21.3	88	17	19.3
Latin American2	2170	42	1.9	1644	30	1.8
Education
< Junior high school	1722	46	2.7	1310	29	2.2
Some high school	441	66	15.0	390	49	12.6
High School Graduate	475	77	16.2	666	128	19.2
Vocational, some college	606	126	20.8	1159	242	20.9
≥college	480	90	18.8	1278	296	23.2
Missing	305	3	1.0	212	/	/
Tobacco smoking status
Never	493	57	11.6	1813	221	12.2
Ever	3536	351	9.9	3196	522	16.3
Missing	/	/		6	1
Alcohol Drinking status
Never	568	34	6.0	1505	80	5.3
Ever	3457	373	10.8	3506	663	18.9
Missing	4	1		4	1

¹Ever marijuana smoking was defined differently in the studies: the Seattle, Houston and Los Angeles studies (‘ever’ use), Latin America study (≥once/week for 6 months) and Tampa study (≥once/day for 1 year).

²The Latin America study did not assess race/ethnicity, thus we classified the subjects as a separate category “Latin Americans”.