Table 2. The Newcastle-Ottawa Quality Assessment Scale was used to assess the eligibility of cohort and cross-sectional studies.

Author and year of publication	Type of the study	Selection (maximum 4 stars)	Comparability (maximum 2 stars)	Outcome (maximum 3 stars)
Baek et al. 2021 [3]	Cohort study	****	**	***
Hall et al. 2015 [5]	Cohort study	****	*	***
Kang et al. 2013 [4]	Cross-sectional study	****	*	***
Myers et al. 2022 [2]	Cohort study	****	*	**
Skogseth et al. 2015 [15]	Cohort study	****	**	*
Hall et al. 2016 [6]	Cohort study	****	**	***