TABLE 2.
Risk of bias assessment using Cochrane Tool to Assess Risk of Bias in Cohort Studies.
| Article | 1 Was selection of exposed and non-exposed cohorts drawn from the same population? | 2 Can we be confident in the assessment of exposure? | 3 Did the study match exposed and unexposed for all variables that are associated with the outcome of interest or did the statistical analysis adjust for these prognostic variables? | 4 Can we be confident in the assessment of the presence or absence of prognostic factors? | 5 Can we be confident in the assessment of outcome? | 6 Was the follow up of cohorts adequate? | 7 Were co-interventions similar between groups? | Sum | Quality |
|---|---|---|---|---|---|---|---|---|---|
| Nyberg and Gustafson, (1997) | 3 | 2 | 3 | 2 | 3 | 2 | 2 | 17 | Good |
| Yates et al. (2002) | 3 | 2 | 2 | 2 | 3 | 3 | 2 | 17 | Good |
| Lamb et al. (2003) | 3 | 2 | 3 | 2 | 1 | 3 | 2 | 16 | Acceptable |
| Olsson et al. (2005) | 3 | 2 | 3 | 2 | 3 | 2 | 2 | 17 | Good |
| Mackintosh et al. (2006) | 3 | 2 | 3 | 2 | 2 | 3 | 2 | 17 | Good |
| Wada et al. (2007) | 3 | 2 | 3 | 2 | 3 | 3 | 2 | 18 | Good |
| Ashburn et al. (2008) | 3 | 2 | 3 | 2 | 3 | 3 | 2 | 18 | Good |
| Kerse et al. (2008) | 3 | 2 | 3 | 2 | 3 | 3 | 2 | 18 | Good |
| Divani et al. (2009) | 3 | 2 | 3 | 2 | 3 | 3 | 2 | 18 | Good |
| Maeda et al. (2009) | 3 | 2 | 2 | 2 | 2 | 2 | 2 | 15 | Acceptable |
| Persson et al. (2011) | 3 | 2 | 3 | 2 | 3 | 3 | 2 | 18 | Good |
| Simpson et al. (2011) | 3 | 2 | 3 | 2 | 3 | 3 | 2 | 18 | Good |
| Anna and Karin (2012) | 3 | 2 | 2 | 2 | 2 | 2 | 2 | 15 | Acceptable |
| Alemdaroglu et al. (2012) | 3 | 2 | 3 | 2 | 3 | 3 | 2 | 18 | Good |
| Blennerhassett et al. (2012) | 3 | 2 | 2 | 2 | 3 | 3 | 2 | 17 | Good |
| Jalayondeja et al. (2014) | 3 | 2 | 3 | 2 | 2 | 3 | 2 | 17 | Good |
| Breisinger et al. (2014) | 3 | 2 | 3 | 3 | 3 | 2 | 2 | 18 | Good |
| Callaly et al. (2015) | 3 | 2 | 3 | 2 | 2 | 3 | 2 | 17 | Good |
| Mansfield et al. (2015) | 3 | 2 | 3 | 3 | 2 | 3 | 2 | 18 | Good |
| Goljar et al. (2016) | 3 | 2 | 3 | 2 | 1 | 3 | 2 | 16 | Acceptable |
| Pinto et al. (2016) | 3 | 2 | 2 | 2 | 3 | 3 | 2 | 17 | Good |
| Taylor-Pilliae et al. (2016) | 1 | 3 | 2 | 3 | 2 | 1 | 2 | 14 | Acceptable |
| Yoshimoto et al. (2016) | 3 | 2 | 2 | 2 | 3 | 3 | 2 | 17 | Good |
| Wei et al. (2017) | 3 | 2 | 3 | 3 | 2 | 3 | 2 | 18 | Good |
| Lee and Jung, (2017) | 3 | 2 | 3 | 3 | 2 | 3 | 2 | 18 | Good |
| Foster et al. (2018) | 3 | 2 | 3 | 3 | 2 | 2 | 2 | 17 | Good |
| Persson et al. (2018) | 3 | 3 | 3 | 2 | 2 | 2 | 2 | 17 | Good |