Table 3.

Subgroup analysis of the prognostic value of PD-L1 in OS and DFS in CCA.

Subgroup factors	No. of studies	No. of patients	HR (95% CI)	p	Effects model	Heterogeneity
						I 2 (%)	p
Overall survival
Total	17	1982	1.58 (1.30-1.92)	<0.001	REM	65.7	<0.001
Ethnicity
Caucasian	5	363	2.14 (1.52-3.02)	<0.001	FEM	11.8	0.338
Asian	12	1619	1.49 (1.20-1.84)	<0.001	REM	70.7	<0.001
Treatment
Surgery	16	1956	1.61 (1.32-1.95)	<0.001	REM	67.0	<0.001
Nonsurgery	1	26	0.70 (0.19-2.60)	0.595	—	—	—
Tumor location
iCCA	5	844	1.31 (0.88-1.95)	0.180	REM	76.9	0.002
eCCA	8	719	1.71 (1.25-2.36)	<0.001	REM	63.1	0.008
CCA	4	419	1.98 (1.47-2.65)	<0.001	FEM	44.2	0.146
Disease-free survival
Total	7	896	1.03 (0.68-1.55)	0.895	REM	72.6	0.001
Ethnicity
Caucasian	1	26	1.13 (0.55-2.34)	0.742	—	—	—
Asian	6	870	1.00 (0.62-1.61)	0.991	REM	77.2	0.001
Treatment
Surgery	5	840	0.97 (0.56-1.69)	0.911	REM	81.7	<0.001
Non-surgery	2	56	1.12 (0.67-1.85)	0.667	FEM	0	0.965
Tumor location
iCCA	2	512	1.02 (0.36-2.92)	0.972	REM	92.2	<0.001
eCCA	3	328	0. (0.40-2.03)	0.800	REM	77.1	0.013
CCA	2	56	1.12 (0.67-1.85)	0.667	FEM	0	0.965

FEM: fixed-effects model; REM: random-effects model.