Table 3. Meta-analysis results of the associations of increased Nrf2 expression with clinicopathological parameters.

Clinicopathological parameter	Ref	Overall OR (95%CI)	P-value	Heterogeneity test (I2, P-value)
Gender (male vs female)	[18–20], [22], [24, 25], [30]	1.28 (0.73–2.24)	0.392	(56.2%, 0.033)
Differentiation (poor VS well)	[17–20], [24, 25]	2.72 (1.30–5.70)	0.008	(60.8%, 0.026)
Tumor size (T3–4 vs T1–2)	[17], [19], [22], [25]	2.11 (0.88–5.03)	0.094	(75.9%, 0.006)
Lymph node metastasis (yes vs no)	[17–19] ,[25]	2.07 (1.13–3.78)	0.018	(42.6%, 0.156)
Distant metastasis (yes vs no)	[18], [22], [30]	8.21 (1.57–43.00)	0.013	(57.8%, 0.094)
Clinical stage (III-IV vs I-II)	[17–20], [24]	3.37 (1.98–5.73)	0.000	(24.2%, 0.260)