TABLE 3.

Overall effects and subgroup analysis of progression-free survival.

Subgroup analysis		No. of studies	HR	95%CI	p	Heterogeneity (I2) (%)
Overall		15	0.89	0.75–1.06	0.185	91.1
Line of therapy	First line	9	0.83	0.68–1.01	0.062	91.3
	Non-first line	6	1.02	0.72–1.46	0.901	91.7
Therapeutic schedules	PD-1/PD-L1 + Chemotherapy vs. Chemotherapy	8	0.68	0.62–0.76	<0.001	60.0
	PD-1/PD-L1 vs. Chemotherapy	8	1.18	0.94–1.47	0.146	86.8
Tumour types	E	8	0.78	0.64–0.95	0.015	86.4
	GEJ	2	0.89	0.44–1.81	0.755	65.8
	G	2	1.16	0.44–3.09	0.759	95.9
Age	< 65 years	5	0.75	0.50–1.14	0.179	91.9
	≥ 65 years	5	0.74	0.55–1.00	0.049	74.9
ECOG performance status	0	5	0.73	0.45–1.19	0.208	89.0
	1	5	0.76	0.55–1.04	0.088	87.5
Sex	Male	5	0.71	0.51–0.98	0.037	90.1
	Female	5	0.98	0.57–1.68	0.932	83.8
Geographical region	Asia	8	0.84	0.61–1.16	0.301	92.5
	Non-Asia	2	0.89	0.52–1.53	0.681	78.6
TPS	TPS < 1%	3	0.93	0.47–1.86	0.836	94.6
	TPS ≥ 1%	4	0.90	0.50–1.60	0.720	83.2
CPS	CPS <	2	0.86	0.65–1.14	0.297	4.4
	CPS ≥ 1	5	0.94	0.69–1.27	0.671	92.6
	CPS < 10	2	0.68	0.48–0.97	0.031	68.2
	CPS ≥ 10	5	0.72	0.58–0.91	0.005	67.4

HR, hazard ratio; CI, confidence interval; ECOG, Eastern Cooperative Oncology Group; PD-1, programmed death-1 receptor; PD-L1, programmed death ligand-1; TPS, PD-L1 tumour proportion score; CPS, PD-L1 combined positive score; E, esophageal cancer; GEJ, gastroesophageal junction cancer; G, gastric cancer.