Table 3.
Levels operated in included studies
| Single level | 1–2 levels | Multilevel |
|---|---|---|
| Zhang et al., 2023 | Zhang et al., 2021 | Martinez‐Ferrer et al. 2013 |
| Bae et al. 2017 | Li et al., 2022 | |
| Xiong et al. 2021 | Ren et al. 2015 | |
| Ju & Liu 2023 |
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