Table 5.

Subgroup analysis of studies on periodontitis and esophageal cancer

Subgroup	No. of studies	Heterogeneity		Model	Meta-analysis
		I2 (95%CI)	p		HR	95%CI	p
Overall analysis	4	60% (0%-87%)	0.06	Random	1.79	1.15-2.79	0.009
Research quality
Medium	2	0%	0.85	Random	3.37	1.83-6.22	<0.0001
High	2	0%	0.65	Random	1.35	1.04-1.75	0.03
Mean age
<50	2	59% (0%-90%)	0.12	Random	1.81	0.67-4.88	0.24
≥50	2	71%	0.06	Random	2.12	1.01-4.45	0.05
Sex
Male	2	0%	0.88	Random	1.41	1.08-1.83	0.01
Female	2	75% (0%-94%)	0.05	Random	1.37	0.17-11.02	0.77
Adjusted covariates
With smoking status	3	63% (0%-89%)	0.07	Random	2.28	1.16-4.49	0.02
With socio-economic status	2	0%	0.85	Random	3.37	1.83-6.22	<0.0001

No. of studies: the number of studies.