Table II.
Summary of the subgroup meta-analysis.
| Heterogeneity | |||||||
|---|---|---|---|---|---|---|---|
| Analysis | N | References | Random-effects model HR (95% CI) | Fixed-effects model HR (95% CI) | I², % | P-value | P-value (between groups) |
| Subgroup 1: Study design | 0.210 | ||||||
| Retrospective | 7 | (26,27,29,30,32-34) | 1.47 (1.17-1.84) | 1.47 (1.17-1.84) | 0.00 | 0.817 | |
| Prospective | 2 | (28,31) | 1.40 (0.93-2.10) | 1.25 (1.10-1.40) | 57.70 | 0.124 | |
| Subgroup 2: Therapy | 0.158 | ||||||
| SBRT only | 5 | (27,28,30,31,33) | 1.25 (1.11-1.40) | 1.25 (1.11-1.40) | 0.00 | 0.577 | |
| Combined | 4 | (26,29,32,34) | 1.52 (1.18-1.95) | 1.52 (1.18-1.95) | 0.00 | 0.575 | |
| Subgroup 3: Stage | 0.147 | ||||||
| Early | 4 | (27,30,31,33) | 1.22 (1.08-1.38) | 1.22 (1.08-1.38) | 0.00 | 0.914 | |
| Advanced | 3 | (29,32,34) | 1.56 (1.21-2.02) | 1.56 (1.21-2.02) | 0.00 | 0.553 | |
| All stages | 2 | (26,28) | 1.56 (0.84-2.90) | 1.64 (1.00-2.69) | 23.90 | 0.252 | |
| Subgroup 4: Cut-off value | 0.051 | ||||||
| NLR ≤3 | 5 | (26,27,30,31,33) | 1.22 (1.08-1.38) | 1.22 (1.08-1.38) | 0.00 | 0.914 | |
| NLR >3 | 4 | (28,29,32,34) | 1.58 (1.26-1.98) | 1.58 (1.26-1.98) | 0.00 | 0.639 | |
| Subgroup 5: Tumor location | 0.230 | ||||||
| NSCLC | 4 | (27,28,31,33) | 1.25 (1.11-1.41) | 1.25 (1.11-1.41) | 0.00 | 0.440 | |
| HCC | 2 | (26,30) | 1.04 (0.58-1.84) | 1.04 (0.58-1.84) | 0.00 | 0.849 | |
| Others | 3 | (29,32,34) | 1.56 (1.21-2.02) | 1.56 (1.21-2.02) | 0.00 | 0.553 | |
| Subgroup 6: Ethnicity | 0.447 | ||||||
| Caucasian | 7 | (27-29,31-34) | 1.33 (1.17-1.51) | 1.30 (1.17-1.45) | 4.00 | 0.396 | |
| Asian | 2 | (26,29) | 1.04 (0.58-1.84) | 1.04 (0.58-1.84) | 0.00 | 0.849 | |
| Subgroup 7: Sample size | 0.941 | ||||||
| ≤100 | 4 | (26,29,30,33) | 1.31 (0.81-2.12) | 1.31 (0.81-2.12) | 0.00 | 0.448 | |
| >100 | 5 | (27,28,31,32,34) | 1.31 (1.16-1.48) | 1.29 (1.16-1.44) | 4.90 | 0.379 | |
CI, confidence interval; HR, hazard ratio; NLR, neutrophil-to-lymphocyte ratio; SBRT, stereotactic body radiation therapy; NSCLC, non-small cell lung cancer; HCC, hepatocellular carcinoma.