Table 3 Risk of bias analysis of included studies
Study | Representativeness | Selection of the non exposed cohort | Ascertainment of exposure | Demonstration that outcome of interest was not present at start of study | Control for confounding factors | Assessment of outcome | Follow up long enough | Adequacy of follow up | NOS score |
|---|---|---|---|---|---|---|---|---|---|
Behanova 2021 [12] | * | * | * | * | − | * | * | – | 6 |
Rutenberg 2021 [13] | * | * | * | * | ** | * | * | – | 8 |
Tian 2020 [23] | * | * | * | * | – | * | * | – | 6 |
Lee 2020 [22] | * | * | * | * | ** | * | * | - | 8 |
Madsen 2019 [21] | * | * | * | * | ** | * | * | – | 8 |
Galbraith 2019 [20] | * | * | * | * | ** | * | * | – | 8 |
Chandran 2018 [19] | * | * | * | * | * | * | * | – | 7 |
Martinez-Laguna 2017 [18] | * | * | * | * | ** | * | * | – | 8 |
Lopez-de-Andrés 2016 [23] | * | * | * | * | ** | * | * | – | 8 |
Golinvaux 2015 [14] | * | * | * | * | ** | * | – | – | 7 |
Ekstrom 2013 [27] | * | * | * | * | - | - | * | – | 5 |
Wang 2013 [28] | * | * | * | * | - | * | * | – | 6 |
Huang 2012 [26] | * | * | * | * | - | * | * | – | 6 |
Gulcelik 2011 [24] | * | * | * | * | ** | * | * | – | 8 |
Norris 2011 [25] | * | * | * | * | * | * | * | – | 7 |
Liebermann 2007 [15] | * | * | * | * | – | * | – | – | 5 |