Table 1.

Risk of bias assessment of nonrandomized studies included in the meta-analysis using the Newcastle-Ottawa

Study	Yr	Selection				Comparability		Outcomes
		Cohort representability	Selection of non-exposed cohort	Ascertainment of exposure	Outcome not present at baseline	Comparability of cohorts for important factors	Comparability of cohorts for other variables	Assessment of outcome	Follow-up long-enough for outcome	Adequacy of follow-up	Overall risk of bias
Fischer	2018	*	*	*	*	*		*	*	*	Low
Urena	2014	*	*	*	*			*	*	*	Low
Dizon	2015	*	*	*	*		*	*	*		Low
Toviabrodie	2017		*	*	*	*	*	*	*	*	Low
Doshi	2018	*	*	*	*	*	*	*			Low
Bacik	2018			*	*	*		*	*		Moderate

Yr: Year; *: Availability of variables.