Author (Year)	Selection	Comparability	Exposure/Outcome
Cross-Sectional studies (n = 18)
James, 1990 [17]	*****	*	***
Bjorvantn, 2012 [19]	****	**	***
Øyane, 2013 [20]	*****	**	***
Hall, 2018 [25]	*****	*	***
Booker, 2018 [26]	*****	*	***
Park, 2020 [34]	*****	*	***
Ruggiero, 2003 [18]	*****	*	**
Gong, 2014 [22]	*****	*	**
Thun, 2014 [21]	*****	*	**
Togo, 2017 [24]	*****	*	**
Dai, 2019 [31]	*****	*	**
Khade, 2019 [28]	*****	*	**
Mbanga, 2019 [29]	*****	*	**
Tahghighi, 2019 [27]	*****	*	**
Bilge, 2020 [32]	*****	*	**
Choi, 2020 [33]	*****	*	**
Yuxin li, 2022 [36]	*****	*	**
Bukhari, 2019 [30]	**	*	**
Cohort studies (n = 2)
Berthelsen, 2015 [23]	*****	**	***
Vitale, 2022 [35]	*****	*	**
* = star. Green highlight = 9 stars or more. Yellow highlight = 7 or 8 stars. Red highlight = 6 stars or fewer.