Table 2.
Risk of bias using the modified Newcastle-Ottawa Scale.
| Study | Selection | Comparability | Outcome | Score | |||||
|---|---|---|---|---|---|---|---|---|---|
| Representativeness of exposed cohort | Selection of non-exposed cohort | Exposure | Outcome of interest not present at start | Comparability of PRFA vs. SRFA | Assessment of outcome | Follow-up | Adequacy of follow-up | ||
| Eun, H. S | Truly representative | Same | Surgical records | Yes | Restricted, matched | Record linkage | Yes | Complete | 9⋆ |
| Chen, S | Truly representative | Same | Surgical records | Yes | Unclear | Record linkage | Yes | Unclear | 7⋆ |
| Khan, M. R | Truly representative | Same | Surgical records | Yes | Restricted, matched | Record linkage | Yes | Complete | 9⋆ |
| Li, J | Truly representative | Same | Surgical records | Yes | Restricted, matched | Record linkage | Yes | Unclear | 8⋆ |
| Hirooka, M | Truly representative | Same | Surgical records | Yes | Not restricted, matched | Record linkage | Yes | Unclear | 7⋆ |
| Sherif, Z | Truly representative | Same | Surgical records | Yes | Restricted, matched | Record linkage | Yes | Complete | 9⋆ |
| Zhang, W | Truly representative | Same | Surgical records | Yes | Restrictions, matched | Record linkage | Yes | Complete | 8⋆ |
| Curley, S. A | Truly representative | Same | Surgical records | Yes | Unclear | Record linkage | Yes | Complete | 8⋆ |
| Raut, C. P | Truly representative | Same | Surgical records | Yes | Restrictions, matched | Record linkage | Yes | Complete | 8⋆ |
| Huang, J. W | Truly representative | Same | Surgical records | Yes | Restrictions, matched | Record linkage | Yes | Complete | 9⋆ |
PRFA, percutaneous radiofrequency ablation; SRFA, surgical radiofrequency ablation.