Table 2. Prevalence rates and odds ratios for esophageal cancer among sample subjects by oral cancer location.

Presence of esophageal cancer	Subjects with oral cancer						Comparison subjects N = 29,650
	Oral cavity N = 1893		Oropharynx N = 372		Hypopharyngeal N = 450
	No.	Percent (%)	No.	Percent (%)	No.	Percent (%)	No.	Percent (%)
Yes	14	0.74	6	1.61	40	8.89	12	0.04
Odds ratio a (95% confidence interval)	18.41*** (8.50∼39.85)		40.49*** (15.11∼108.64)		240.96*** (125.49∼462.69)		1.00

Notes: ^aOdds ratios were calculated using the conditional logistic regression model (conditioned on age group and gender);

^*** p<0.001.