Table 2.
Summary of subgroup analysis results in studies that reported OS stratified by PD-L1 status
| Subgroup | No of studies | Heterogeneity
|
Analysis model | Effect size
|
HR for OS (95% CI) | ||
|---|---|---|---|---|---|---|---|
| P-value | I2 (%) | Z | P-value | ||||
| Antibody source | |||||||
| Mouse | 3 | 0.48 | 0 | Fixed effect | 4.16 | <0.0001 | 1.85 (1.38, 2.47) |
| Rabbit | 4 | 0.008 | 75 | Random effect | 0.86 | 0.39 | 1.38 (0.66, 2.90) |
| NA | 1 | 1.42 (0.53, 3.80) | |||||
| Antibody type | |||||||
| Monoclonal | 4 | 0.67 | 0 | Fixed effect | 4.32 | <0.0001 | 1.87 (1.41, 2.47) |
| Polyclonal | 3 | 0.005 | 81 | Random effect | 0.53 | 0.60 | 1.26 (0.54, 2.94) |
| NA | 1 | 1.42 (0.53, 3.80) | |||||
| Methods | |||||||
| IHC | 7 | 0.004 | 68 | Random effect | 2.25 | 0.02 | |
| ELISA | 1 | 1.42 (0.53, 3.80) | |||||
Abbreviations: CI, confidence interval; ELISA, enzyme-linked immunosorbent assay; HR, hazard ratio; IHC, immunohistochemistry; NA, not available; OS, overall survival; PD-L1, programmed cell death-ligand 1.