Table 1. Characteristics of included studies.
| Reference | Year | Region | Study design | Sample size | Bismuth–Corlette classification | Laparoscopic or robotic surgery | Age: median(range)/mean±SD | Gender: male/female | |||
|---|---|---|---|---|---|---|---|---|---|---|---|
| MIS | OS | MIS | OS | MIS | OS | ||||||
| Xu et al. [31] | 2016 | China | Retrospective cohort | 10 | 32 | Mixed | Robotic | 54(36–77) | 59(37–77) | 8/2 | 20/12 |
| Zhang et al. [32] | 2019 | China | Retrospective cohort | 14 | 9 | Mixed | Laparoscopic | 65.4±8.9 | 65.4±6.9 | 7/7 | 3/6 |
| Jiang et al. [33] | 2020 | China | Retrospective cohort | 54 | 54 | Bismuth type I | Laparoscopic | 67.7±2.3 | 67.7±2.2 | 29/25 | 28/26 |
| Zhu et al. [34] | 2018 | China | Retrospective cohort | 10 | 24 | Bismuth type I | Laparoscopic | 62.0±7.4 | 59.2±8.1 | 6/4 | 13/11 |
| Gong et al. [35] | 2014 | China | Retrospective cohort | 14 | 5 | Mixed | Laparoscopic | 58.5±3.6 | 54.9±4.5 | 8/6 | 3/2 |
| Chou et al. [36] | 2020 | China | Retrospective cohort | 16 | 31 | Mixed | Robotic | 68.0±7.0 | 60.0±9.0 | 11/5 | 20/11 |
| Duan et al. [37] | 2019 | China | Retrospective cohort | 13 | 14 | Bismuth type I | Laparoscopic | 59.2±8.0 | 62.0±7.4 | N/A | 8/6 |
| Chai et al. [38] | 2019 | China | Retrospective cohort | 17 | 17 | Bismuth type IIIb | Laparoscopic | N/A | N/A | N/A | N/A |
| Ratti et al. [39] | 2020 | Italy | Retrospective cohort | 16 | 32 | Mixed | Laparoscopic | 61(48–81) | 63(43–80) | 8/8 | 17/15 |