Table 2:
Risk of bias assessment based on information presented in the publications
| Study | Sequence generation | Allocation concealment | Blinding | Incomplete outcome reporting | Selective outcome reporting |
|---|---|---|---|---|---|
| Izbicki [23] | Clear | Unclear | Not possible | Yes: No ITTA | No |
| Sugi [27] | Unclear | Unclear | Not possible | Unclear | No |
| Wu [13] | Unclear | Unclear | Not possible | Yes: No ITTA | No |
| ACOSOG [26] | Unclear | Unclear | Not possible | Yes: No ITTA | No |
| Zhang [15] | Unclear | Unclear | Not possible | Unclear | No |
ITTA: intention to treat analysis.