Table 2 The assessment of the risk of bias in included studies using the Newcastle–Ottawa scale
Study | Year | Selection (0–4) | Comparability (0–2) | Outcome (0–3) | Total | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
REC | SNEC | AE | DO | SC | AF | AO | FU | AFU | |||
Konczalla L | 2019 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | 0 | 6 |
Woestemeier A | 2018 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | 0 | 6 |
Tanaka M | 2015 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | 1 | 7 |
Matsushita D | 2015 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | 0 | 6 |
Reeh M | 2015 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 1 | 0 | 6 |
Sclafani F | 2014 | 1 | 1 | 0 | 1 | 0 | 0 | 1 | 0 | 0 | 4 |
Hiraiwa K | 2008 | 1 | 1 | 0 | 1 | 0 | 0 | 1 | 0 | 0 | 4 |