Table 2.

Newcastle-Ottawa Scale for risk of bias assessment of the included studies (scores ≥ 7–9, 4–6, <4 are considered low, intermediate, and high risk, respectively).

Study	Selection				Comparability	Outcome			Overall
	Representativeness of Exposed Cohort	Selection of Non-Exposed	Ascertainment of Exposure	Outcome Not Present at Start		Assessment of Outcome	Adequate Follow-Up Length	Adequacy of Follow-Up
Moschovas 2021 [9]	*	*	*	*	**	*	-	*	8/9
Ju 2021 [10]	*	*	*	*	**	*	-	*	8/9
Saidian 2020 [11]	*	*	*	*	*-	*	-	*	7/9
Lenfant 2020 [16]	*	*	*	*	*-	*	*	*	8/9
Vigneswaran 2020 [17]	*	*	*	*	*-	*	-	*	7/9

* Equals one point, with a total of 9 points (* for each item and ** equals 2 points for comparability).