Assessment of quality of included studies with the Newcastle–Ottawa Scale8
| Study | Component; score | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Selection | Comparability of cohorts on basis of design or analysis | Exposure | Study quality | |||||||
| Representativeness of exposed cohort | Selection of nonexposed cohort | Ascertainment of exposure | Demonstration that outcome of interest not present at start of study | Assessment of outcome | Enough follow-up time length for outcome to occur | Adequacy of follow-up of cohorts | Total score | Interpretation | ||
| Cohort | ||||||||||
| Ke et al.,11 | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 1 | 9 | Good |
| Hallac et al.,5 | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 1 | 9 | Good |
| Hirono et al.,12 | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 1 | 9 | Good |
| Kusakabe et al.,13 | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 1 | 9 | Good |
| Riediger et al.,14 | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 0 | 8 | Good |
| Mackay et al.,15 | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 0 | 8 | Good |
| Nordback et al.,16 | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 1 | 9 | Good |
| Falconi et al.,17 | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 0 | 8 | Good |
| Rault et al.,18 | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 0 | 8 | Good |
| Nakamura et al.,4 | 1 | 1 | 1 | 1 | 2 | 1 | 0 | 0 | 7 | Good |
| Neophytou et al.,19 | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 1 | 9 | Good |
| Okano et al.,20 | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 1 | 9 | Good |
| Maignan et al.,21 | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 1 | 9 | Good |
| Kachare et al.,22 | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 1 | 9 | Good |
| Lim et al.,23 | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 1 | 9 | Good |
| Miyamoto et al.,24 | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 1 | 9 | Good |
| Sikkens et al.,3 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 8 | Good |
| Belyaev et al.,25 | 1 | 1 | 1 | 1 | 2 | 1 | 1 | 1 | 9 | Good |
| Selection | Comparability of subjects in different outcome groups on basis of design or analysis | Exposure | Study quality | |||||||
| Representativeness of sample | Sample size | Non-respondents | Ascertainment of exposure | Assessment of outcome | Statistical test | Total score | Interpretation | |||
| Cross-sectional | ||||||||||
| Yuasa et al.,2 | 1 | 1 | 1 | 2 | 1 | 2 | 0 | 8 | Good | |
| Jang et al.,26 | 1 | 1 | 1 | 2 | 1 | 2 | 1 | 9 | Very good | |