Allele Frequency of ABO Blood Group Antigen and the Risk of Esophageal Cancer

Table 3

Presence of B antigen (B and AB blood groups) and absence of B antigen (O and A blood groups); Chi-square test with significance and odd ratio.

	𝑛	Presence of B (B + AB)	Absence of B (O + A)	Chi-square	𝑃 value	Odds ratio	CI = 95%
All
Cases	480	284 (59.17)	196 (40.83)	16.58	<0.0001	1.69	1.31–2.19
Control	480	221 (46.04)	259 (53.96)
Male
Cases	252	147 (58.33)	105 (41.67)	6.24	0.012	1.57	1.10–2.24
Control	240	113 (47.1)	127 (52.9)
Female
Cases	228	137 (60.1)	91 (39.9)	10.67	0.001	1.84	1.27–2.65
Control	240	108 (45)	132 (55)
Site of cancer (case)
Upper	86	45 (52.3)	41 (47.7)	0.212	0.645
Middle	192	109 (56.77)	83 (43.23)	1.833	0.175
Lower	202	130 (64.36)	72 (35.64)	8.248	0.004

Degree of freedom = 1.
Values in parentheses are percentages.