Table 1. Distribution of cases of oral and pharyngeal cancer and laryngeal cancer and controls according to selected variables (International Head and Neck Cancer Epidemiology (INHANCE) consortium).

	Oral and pharyngeal cases	(%)	Controls	(%)	Laryngeal cases	(%)	Controls	(%)
Age (years)
<40	208	4.7	681	5.6	26	1.7	681	5.6
⩾40 to ⩽44	194	4.4	563	4.6	45	2.9	563	4.6
⩾45 to ⩽49	446	10.1	949	7.7	123	8.0	949	7.7
⩾50 to ⩽54	645	14.6	1731	14.1	188	12.2	1731	14.1
⩾55 to ⩽59	816	18.5	2079	17.0	271	17.5	2079	17.0
⩾60 to ⩽64	713	16.2	2029	16.6	290	18.8	2029	16.6
⩾65 to ⩽69	658	14.9	1931	15.8	279	18.1	1931	15.8
⩾70 to ⩽74	474	10.7	1540	12.6	227	14.7	1540	12.6
⩾75	260	5.9	743	6.1	96	6.2	743	6.1
Missing	0	0.0	2	0.0	0	0.0	2	0.0
χ2 (P-value)a	42.0 (<0.001)				66.5 (<0.001)
Sex
Female	1187	26.9	3541	28.9	244	15.8	3541	28.9
Male	3223	73.0	8702	71.0	1300	84.1	8702	71.0
Missing	4	0.1	5	0.0	1	0.1	5	0.0
χ2 (P-value)a	6.3 (0.012)				117.8 (<0.001)
Race
Black	387	8.8	535	4.4	116	7.5	535	4.4
Others (with Asians)	463	10.5	3089	25.2	101	6.5	3089	25.2
White (with Hispanics)	3555	80.5	8596	70.2	1324	85.7	8596	70.2
Missing	9	0.2	28	0.2	4	0.3	28	0.2
χ2 (P-value)a	491.5 (<0.001)				281.7 (<0.001)
Study name
Boston	313	7.1	611	5.0	71	4.6	611	5.0
Buffalo	396	9.0	1190	9.7	168	10.9	1190	9.7
Italy Multicenter
Milan	169	3.8	621	5.1	24	1.6	621	5.1
Pordenone	471	10.7	1528	12.5	409	26.5	1528	12.5
Latina	95	2.2	425	3.5	0	0.0	425	3.5
Japan (2001–2005)	407	9.2	3002	24.5	86	5.6	3002	24.5
Los Angeles	246	5.6	828	6.8	60	3.9	828	6.8
Milan (2006–2009)	131	3.0	691	5.6	200	12.9	691	5.6
MSKCC	74	1.7	123	1.0	32	2.1	123	1.0
North Carolina (2002–2006)	687	15.6	1120	9.1	374	24.2	1120	9.1
Switzerland	367	8.3	877	7.2	121	7.8	877	7.2
US Multicenter
Atlanta	129	2.9	134	1.1	0	0.0	134	1.1
New Jersey	467	10.6	459	3.7	0	0.0	459	3.7
Los Angeles	398	9.0	501	4.1	0	0.0	501	4.1
San Francisco	64	1.4	138	1.1	0	0.0	138	1.1
χ2 (P-value)a	1121.5 (<0.001)				1092.0 (<0.001)
Education
⩽Junior high school	863	19.6	2723	22.2	603	39.0	2723	22.2
Some high school	885	20.0	1240	10.1	258	16.7	1240	10.1
High school graduate	588	13.3	1267	10.3	237	15.3	1267	10.3
Technical school, some college	1174	26.6	2305	18.8	214	13.9	2305	18.8
⩾College graduate	491	11.1	1703	13.9	145	9.4	1703	13.9
Missing	413	9.4	3010	24.6	88	5.7	3010	24.6
χ2 (P-value)a	766.2 (<0.001)				503.7 (<0.001)
Cigarette smoking status
Never	806	18.3	4868	39.7	90	5.8	4868	39.7
Former	1387	31.4	4330	35.4	707	45.8	4330	35.4
Current	2210	50.1	2986	24.4	735	47.6	2986	24.4
Missing	11	0.2	64	0.5	13	0.8	64	0.5
χ2 (P-value)a	1139.6 (<0.001)				755.3 (<0.001)
Cigarette intensity (cigarettes per day)
Never smoker	806	18.3	4868	39.7	91	5.9	4868	39.7
>0 to ⩽10	471	10.7	1949	15.9	149	9.6	1949	15.9
>10 to ⩽20	1466	33.2	3169	25.9	628	40.6	3169	25.9
>20	1633	37.0	2137	17.4	661	42.8	2137	17.4
Missing	38	0.9	125	1.0	16	1.0	125	1.0
χ2 (P-value)a	1111.2 (<0.001)				1015.8 (<0.001)
Duration of cigarette smoking (years)
Never smoker	806	18.3	4868	39.7	91	5.9	4868	39.7
>0 to ⩽20	443	10.0	2166	17.7	102	6.6	2166	17.7
>20	3132	71.0	5123	41.8	1343	86.9	5123	41.8
Missing	33	0.7	91	0.7	9	0.6	91	0.7
χ2 (P-value)a	1116.8 (<0.001)				1133.7 (<0.001)
Cigar smoking
Never cigar user	3583	81.2	8545	69.8	1323	85.6	8545	69.8
Ever smoked ⩾100 cigars in a lifetime	394	8.9	636	5.2	118	7.6	636	5.2
Missing	437	9.9	3067	25.0	104	6.7	3067	25.0
χ2 (P-value)a	33.7 (0.008)				2.8 (0.093)
Pipe smoking
Never pipe user	3579	81.1	8327	68.0	1325	85.8	8327	68.0
Ever smoked ⩾100 pipes in a lifetime	399	9.0	864	7.1	115	7.4	864	7.1
Missing	436	9.9	3057	25.0	105	6.8	3057	25.0
χ2 (P-value)a	1.2 (0.027)				2.8 (0.094)
Alcohol consumption (drinks per day)
Never drinker	548	12.4	3156	25.8	187	12.1	3156	25.8
<1	1030	23.3	4022	32.8	250	16.2	4022	32.8
⩾1 to 3	973	22.0	2934	24.0	344	22.3	2934	24.0
⩾3 to 5	647	14.7	1215	9.9	250	16.2	1215	9.9
⩾5	1216	27.5	921	7.5	514	33.3	921	7.5
χ2 (P-value)a	1442.0 (<0.001)				1155.2 (<0.001)

Abbreviation: MSKCC=Memorial Sloan Kettering Cancer Center.

^aMissing values were not considered in the calculation of the χ² test.