Table 2.

Odds ratios for smoking associated with oral cancer relative to OED

Exposure	Cancer (n)	OED (n)	ORa	95% CI	ORadjb	95% CI
Never smoked	32	49	1.0	–	1.0	–
Ever smoked	149	224	1.02	0.62–1.67	0.84	0.41–1.25
Ex-smoker	59	92	0.98	0.57–1.71	0.80	0.43–1.49
Current smoker	90	132	1.04	0.62–1.76	0.65	0.36–1.19
Current smoking
No	91	141	1.0	–	1.0	–
Yes	90	132	1.06	0.73–1.54	0.76	0.49–1.18
Pack-year equivalents of smokingc
0	32	49	1.0	–	1.0	–
>0–<20	40	56	1.09	0.60–2.00	1.01	0.52–1.96
20–<50	56	101	0.85	0.49–1.48	0.58	0.31–1.08
50+	53	67	1.21	0.68–2.15	0.66	0.34–1.29
Trend P			0.71		0.09
Average cigarette equivalents per day c
0	32	49	1.0	–	1.0	–
1–19	38	63	0.92	0.51–1.68	0.82	0.43–1.58
20–39	69	116	0.91	0.53–1.56	0.64	0.35–1.17
40+	42	45	1.43	0.77–2.64	0.76	0.37–1.56
Trend P			0.32		0.30
Years since stopped smoking
Never smoker	32	49	1.0	–	1.0	–
20+ years	29	38	1.17	0.61–2.25	1.08	0.52–2.25
2–19 years	30	54	0.85	0.45–1.60	0.63	0.31–1.27
Current smoker	90	132	1.04	0.62–1.76	0.64	0.35–1.18
Trend P			0.99		0.08
Age started smoking
Never smoker	32	49	1.0	–	1.0	–
>0–<17	61	68	1.37	0.78–2.41	0.85	0.45–1.62
17–19	44	76	0.89	0.50–1.58	0.68	0.35–1.30
20+	44	80	0.84	0.47–1.50	0.65	0.34–1.22
Trend P			0.20		0.13

^aCrude OR

^bOR adjusted for age (four levels), gender, alcohol consumption (four levels), education (three levels), pathology laboratory

^cPack-year and average cigarette equivalents for pipe and cigar smokers based on 1 cigarette = 1/2 pipe = 1/4 cigar