Particular outcome? -ls/are the authors' If not there could be potential issues \vith , conclusions bias. iustifiable? Can the study If not there could be potential issues with 1 results be study quality. applicable to the I target population? Levels of Evidence for Randomized Controlled Trlal ' 1++: High quality randomized controlled trial with verv low bias risk 1+: Hioh quality randomized controlled trial with low bias risk 1-: Randomized controlled trial with high bias risk Ill. Cohort/Case-Control Study CQbQl:t Question Yes No Comment Does the study ask a specific question? Were the If not. there could be potential issues with participants similar bias. enough to one another (aside from factors of interest)? Were the If not, there could be potential issues with participants' bias. characteristics clearly defined? Was it stated that If not, there could be potential issues with there was some bias. blinding of the researchers? Were all If not, there could be potential issues with participants" bias. exposure status compared (including those who dropped out, died, or lost to follow-up)? Were all outcome If not there could be potential issues with measures, study quality. measured using the best available measure for that particular outcome? Was the measure If not there could be potential issues with for the exposure(s) study quality. I reliable?