Table 2. Quality assessment of observational studies.

The quality assessment was done using the Newcastle-Ottawa scale.

Author ID	Selection of participant	Comparability between groups	Outcome and exposure assessment	Overall quality score	Quality grade
Ge et al., 2024 [15]	4	2	3	9	Good
Nezu et al., 2023 [16]	4	2	3	9	Good
Saito et al., 2020 [17]	3	2	3	8	Good
Wagatsuma et al., 2022 [18]	3	1	3	7	Good