Table 1.

Assessment of Risk of Bias

Risk of Bias Domain	Criterion
I. Selection bias	(1) Does the design or analysis control or account for >1 important confounding or modifying variables through matching, stratification, multivariable analysis, or other approaches? (Yes=1; No=0)
II. Attrition and participation bias	(2) If attrition (dropout, loss to follow‐up) or high rate of refusal was a concern, were missing data or characterization of refusers handled appropriately (eg, imputation, descriptions of reasons for refusal and/or drop‐out, comparison of refusers vs nonrefusers)?
III. Reporting bias	(3) Were potential outcomes prespecified by the researchers? Are all prespecified outcomes reported?
IV. Detection bias	(4) Were the outcomes assessed/defined using valid and reliable measures, implemented consistently across all study participants?
	(5) Were confounding variables assessed using valid and reliable measures, implemented consistently across study participants?