TABLE 3.
Quality assessment based on the NOS.
| Study | Year | Selection | Comparability | Outcome | Total score |
|---|---|---|---|---|---|
| Forrest (7) | 2003 | 4 | 2 | 2 | 8 |
| Forrest (14) | 2004 | 4 | 2 | 2 | 8 |
| Forrest (33) | 2005 | 4 | 2 | 2 | 8 |
| Miyazaki (29) | 2015 | 4 | 2 | 2 | 8 |
| Fan (28) | 2016 | 4 | 2 | 1 | 7 |
| Yotsukura (24) | 2016 | 4 | 2 | 2 | 8 |
| Miyazaki (23) | 2017 | 4 | 2 | 2 | 8 |
| Tomita (21) | 2018 | 4 | 2 | 2 | 8 |
| Kasahara (20) | 2019 | 4 | 2 | 2 | 8 |
| Kasahara (18) | 2020 | 4 | 2 | 2 | 8 |
| Takamori (15) | 2021 | 4 | 2 | 2 | 8 |
| Tomita (32) | 2014 | 4 | 2 | 2 | 8 |
| Lindenmann (17) | 2020 | 4 | 2 | 2 | 8 |
| Machida (27) | 2016 | 4 | 2 | 2 | 8 |
| Kawashima (30) | 2015 | 4 | 2 | 2 | 8 |
| Jiang (31) | 2014 | 4 | 2 | 2 | 8 |
| Osugi (26) | 2016 | 4 | 2 | 2 | 8 |
| Su (25) | 2016 | 4 | 2 | 2 | 8 |
| Ni (22) | 2018 | 4 | 2 | 2 | 8 |
| Topkan (19) | 2019 | 3 | 2 | 2 | 7 |
| Kikuchi (16) | 2020 | 3 | 2 | 2 | 7 |
NOS, Newcastle–Ottawa Quality Assessment Scale.