Table 2. Newcastle-Ottawa Scale Scores for Observational Studies.
| Source | Selection | Comparability | Outcome | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Exposed cohort representative | Selection of unexposed | Exposure ascertainment blind or objective? | Outcome not present pre-exposure? | Controlled for other interventions/important confounders? | Similar baseline demographics or other confounders? | Outcome assessment blind or objective? | Follow-up long enough? | Lost to follow-up | |
| Conroy et al,24 2014 | Low risk of bias | High risk of bias | Low risk of bias | Low risk of bias | Low risk of bias | Low risk of bias | Low risk of bias | Low risk of bias | Low risk of bias |
| Corl et al,25 2018 | Low risk of bias | High risk of bias | Low risk of bias | Low risk of bias | High risk of bias | Low risk of bias | High risk of bias | Low risk of bias | Low risk of bias |
| Fogg et al,26 2016 | Low risk of bias | High risk of bias | Low risk of bias | High risk of bias | High risk of bias | High risk of bias | High risk of bias | Low risk of bias | Low risk of bias |
| Hatch et al,27 2016 | Low risk of bias | High risk of bias | Low risk of bias | High risk of bias | High risk of bias | Low risk of bias | Low risk of bias | Low risk of bias | No |
| Kerrey et al,29 2015 | Low risk of bias | High risk of bias | Low risk of bias | High risk of bias | High risk of bias | High risk of bias | Low risk of bias | Low risk of bias | Low risk of bias |
| Lewis et al,1 2018 | Low risk of bias | High risk of bias | Low risk of bias | Low risk of bias | High risk of bias | High risk of bias | High risk of bias | Low risk of bias | Low risk of bias |
| Long et al,30 2017 | Low risk of bias | High risk of bias | Low risk of bias | High risk of bias | High risk of bias | High risk of bias | High risk of bias | Low risk of bias | Low risk of bias |
| Powell et al,31 2018 | Low risk of bias | Low risk of bias | Low risk of bias | Low risk of bias | High risk of bias | High risk of bias | High risk of bias | Low risk of bias | Low risk of bias |
| Smith et al,32 2015 | Low risk of bias | High risk of bias | Low risk of bias | High risk of bias | Low risk of bias | Low risk of bias | Low risk of bias | Low risk of bias | Low risk of bias |
| Szucs et al,33 2019 | Low risk of bias | High risk of bias | Low risk of bias | Low risk of bias | Low risk of bias | Low risk of bias | Low risk of bias | Low risk of bias | Low risk of bias |