Table 2. Summarised hazard ratios.

	Number of studies	Number of patients	Pooled HR (95% CI)	I2 value (%)	P-value	P-value differences a
CD3+
Smallest studiesb	7	1039	0.48 (0.33–0.69)	72	<0.0001	<0.00001
Largest studiesc	4	1985	0.76 (0.55–1.07)	86	0.11
Median follow-up <4 years	5	918	0.53 (0.36–0.78)	65	0.001	<0.000001
Median follow-up >4 years	4	1808	0.83 (0.66–1.04)	59	0.11
Quality score ⩽5	4	741	0.58 (0.30–1.13)	89	0.11	0.11
Quality score >5	7	2301	0.58 (0.41–0.82)	86	0.002
Tissue microarray	5	2223	0.70 (0.51–0.97)	85	0.03	<0.00001
Whole-tissue slides	6	819	0.48 (0.31–0.75)	77	0.001
Hotspots scored	4	671	0.62 (0.37–1.04)	79	0.07	0.73
Representative areas scored	7	2371	0.55 (0.37–0.83)	89	0.004
Ovarian cancer	5	1053	0.53 (0.28–1.01)	92	0.05	0.25
Colorectal cancer	3	1319	0.64 (0.37–1.10)	84	0.11
CD8+
Smallest studiesd	12	2319	0.66 (0.53–0.81)	59	0.0001	0.003
Largest studiese	4	3740	0.82 (0.75–0.91)	0	<0.0001
Median follow-up <4 years	6	1322	0.53 (0.45–0.62)	0	<0.00001	0.0003
Median follow-up >4 years	9	2539	0.76 (0.64–0.90)	48	0.002
Quality score ⩽5	7	2348	0.74 (0.61–0.91)	48	0.004	0.46
Quality score >5	9	3693	0.69 (0.56–0.86)	70	0.0006
Tissue microarray	9	3926	0.71 (0.60–0.85)	61	0.0001	0.53
Whole-tissue slides	7	2133	0.72 (0.55–0.95)	66	0.02
Hotspots scored	5	893	0.75 (0.59–0.97)	37	0.03	0.98
Representative areas scored	11	5166	0.70 (0.58–0.83)	69	<0.0001
Ovarian cancer	4	983	0.69 (0.54–0.88)	49	0.003	0.45
Colorectal cancer	4	2582	0.62 (0.44–0.88)	81	0.007

Abbreviations: CIs=confidence intervals; HRs=hazard ratios.

All analyses were carried out for overall survival only. Median follow-up was not available for all studies.

^aP-values for differences between pairs, bold indicating whether there are statistically significant differences between pooled results from, for instance, small and large studies.

^bn=100–220.

^cn=302–786.

^dn=109–359.

^en=500–1290.