Table 2.
The literature quality assessment.
| References | Design | Newcastle-Ottawa scale (NOS) | |||
|---|---|---|---|---|---|
| Selection | Comparability | Exposure | Total scores | ||
| Sheehan et al. (13) | Retrospective cohort study | 2 | 2 | 2 | 6 |
| Messerer et al. (14) | Retrospective cohort study | 4 | 1 | 2 | 7 |
| Dallapiazza et al. (15) | Retrospective cohort study | 3 | 2 | 3 | 8 |
| Karppinen et al. (16) | Retrospective cohort study | 3 | 1 | 2 | 6 |
| Zaidi et al. (10) | Retrospective cohort study | 3 | 1 | 3 | 7 |
| Pledger et al. (25) | Retrospective cohort study | 4 | 2 | 2 | 8 |
| Little et al. (17) | Prospective cohort study | 4 | 2 | 3 | 9 |
| Haens et al. (26) | Retrospective cohort study | 3 | 1 | 2 | 6 |
| Choe et al. (18) | Retrospective cohort study | 4 | 2 | 2 | 8 |
| Cheng et al. (19) | Retrospective cohort study | 3 | 2 | 2 | 7 |
| Fathalla et al. (20) | Retrospective cohort study | 4 | 1 | 3 | 8 |
| Gao et al. (21) | Retrospective cohort study | 3 | 1 | 3 | 7 |
| Guo-Dong et al. (22) | Retrospective cohort study | 3 | 1 | 2 | 6 |
| Starke et al. (23) | Retrospective cohort study | 3 | 2 | 2 | 7 |
| Sarkar et al. (24) | Retrospective cohort study | 3 | 2 | 2 | 7 |
| Castaño-Leon et al. (11) | Prospective cohort study | 4 | 2 | 2 | 8 |
NOS, Newcastle-Ottawa scale.