Quality Assessment Summary of Findings Risk of Bias Inconsistency Indirectness Imprecision Publication Bias Study Event Rates (%) Relative Effect CI) Estimation of Absolute Effects Time Frame No. of Studies With ASA With ASA/Clopid With ASA With ASA/Clopid CI) Quality of Evidence Death (critical outcome) median follow-up y RCT No serious limitations No serious inconsistency No serious indirectness Imprecise a Undetected RR per b fewer death per (from fewer to more) Moderate Nonfatal stroke (critical outcome) median follow-up y; ischemic stroke and intracranial hemorrhage c RCT No serious limitations No serious inconsistency No serious indirectness No serious imprecision Undetected d e RR CHADS points High per f fewer strokes per (from fewer to fewer) CHADS point per fewer strokes per (from fewer to fewer) CHADS points per fewer strokes per (from fewer to fewer) CHADS points per fewer strokes per (from fewer to fewer) Nonfatal major extracranial bleeds (important outcome) median follow-up y g RCT No serious limitations No serious inconsistency No serious indirectness No serious imprecision Undetected RR per h more bleeds per (from more to more) High e550S Antithrombotic Therapy for Atrial Fibrillation Table Quality Assessment Summary of Findings Risk of Bias Inconsistency Indirectness Imprecision Publication Bias Study Event Rates (%) Relative Effect CI) Estimation of Absolute Effects Time Frame No. of Studies With ASA With ASA/Clopid With ASA With ASA/Clopid CI) Quality of Evidence Systemic embolism (important outcome) median follow-up y RCT No serious limitations No serious inconsistency No serious indirectness Imprecise i Undetected RR per j fewer systemic emboli per (from fewer to more) Moderate See Table and legends for expansion of abbreviations. a The CI does not exclude the possibility of no effect. 