Table 2.

Subgroup analysis of the correlation between PNI and overall survival.

Subgroup	No. of studies	OS hazard ratios (95% CI)	p-value	Heterogeneity
				I 2	p -value
Region
Asia	8	2.69 (1.68–4.32)	< 0.001	64.60%	0.006
No-Asia	4	2.70 (1.93–3.79)	< 0.001	0.00%	0.579
Age group
≤ 65	3	4.75 (2.18–10.32)	< 0.001	63.60%	0.064
>65	8	2.23 (1.71–2.89)	< 0.001	3.500%	0.403
Cut-off value
≤ 45.05	6	2.52 (1.92–3.31)	< 0.001	0.00%	0.614
>45.05	7	2.81 (1.49–5.30)	0.001	72.70%	0.001
Therapy type
ICI	7	2.61 (1.98–3.46)	< 0.001	0.00%	0.450
PD−1	3	2.60 (1.88–3.59)	< 0.001	0.00%	0.732
Combination	6	2.61 (1.98–3.46)	0.005	75.10%	0.001

PD-1, programmed cell death protein-1; CI, confidence interval; ICI, immune checkpoint inhibitor.