Table 2.

Serum folate level (median (25th–75th) and DNA methylation status (n (%)) in the three groups

Variables	Control (n = 200)	EPL (n = 200)	ESCC (n = 200)	p value
Serum folate (μg/L)	29.14 (24.43–36.24)	25.72 (21.29–29.47)a	24.79 (20.73–29.85)a	< 0.001*
No. of p16 methylation	70 (35.0%)	92 (46.0%)b	126 (63.0%)b	< 0.05†
No. of p53 methylation	74 (36.5%)	84 (42.0%)	113 (56.5%)b	< 0.05†

^*p value of Kruskal-Wallis test

^†p value of Chi-square (χ²) test

^aCompared with control group, p < 0.05 (Mann-Whitney U test)

^bCompared with control group, p < 0.05 (Chi-square (χ²) test)