Table 2 Subgroup analysis of univariate and multivariate overall survival
Stratified analysis | Number of studies in univariate analysis | HR with 95% CI | P value | I2 | Number of studies in multivariate analysis | HR with 95% CI | P value | I2 |
|---|---|---|---|---|---|---|---|---|
ALBI grade | ||||||||
 2 vs 1 | 7 | 2.20 (1.83–2.64) |  < 0.01 | 14% | 6 | 2.14 (1.50–3.05) |  < 0.01 | 54% |
 High vs low | 4 | 1.96 (1.45–2.65) |  < 0.01 | 56% | 2 | 2.15 (0.56–8.17) | 0.26 | 80% |
 2–3 vs 1 | 3 | 1.60 (1.34–1.92) |  < 0.01 | 0 | 1 | 1.36 (1.04–1.78) |  |  |
Treatment | ||||||||
 Surgery | 9 | 1.91 (1.64–2.22) |  < 0.01 | 56% | 6 | 1.63 (1.26–2.11) |  < 0.01 | 54% |
 Multiple | 3 | 1.37 (0.86–2.18) | 0.19 | 0 |  |  |  |  |
 MWA | 2 | 3.92 (1.86–8.25) |  < 0.01 | 0 | 2 | 8.87 (2.48–31.71) |  < 0.01 | 0 |
 MWA + surgery |  |  |  |  | 1 | 2.36 (0.98–3.77) |  |  |
Sample size | ||||||||
 Over 200 | 5 | 1.69 (1.50–1.90) |  < 0.01 | 0 | 3 | 1.34 (1.11–1.61) |  < 0.01 | 0 |
 Below 200 | 9 | 2.32 (1.98–2.72) |  < 0.01 | 24% | 6 | 2.56 (1.90–3.45) |  < 0.01 | 17% |
Quality score | ||||||||
 ≥ 8 score | 9 | 1.93 (1.63–2.28) |  < 0.01 | 53% | 7 | 1.68 (1.28–2.20) |  < 0.01 | 59% |
 < 8 score | 5 | 1.84 (1.29–2.62) |  < 0.01 | 42% | 2 | 2.86 (1.55–5.29) |  < 0.01 | 7% |