Table 2.

Bias risk assessment for cohort study/case-control study

Included study	Selection	Comparability	Exposure	Score
Liu SS 2011 [6]	☆☆☆	☆	☆☆	6
Aust H 2012 [7]	☆☆☆☆	☆	☆☆	7
Labaste F 2016 [8]	☆☆☆☆	☆	☆☆	7
Kaushal A 2018 [9]	☆☆☆☆	☆	☆☆	7
Taye MG 2021 [11]	☆☆☆☆	☆☆	☆☆	8
Andualem AA 2022 [12]	☆☆☆☆	☆☆	☆☆	8
Lin F 2022 [13]	☆☆☆	☆☆	☆☆	7
Bang YJ 2023 [14]	☆☆☆	☆☆	☆☆	7
Berhanu M 2023 [15]	☆☆☆☆	☆☆	☆☆	8
Haller K 2023 [16]	☆☆☆	☆	☆☆	6

☆ symbolizes 1 point.