Table 4.

GRADE assessment of certainty of evidence for primary outcomes

Outcome	No. of studies (patients)	Risk of bias	Inconsistency	Indirectness	Imprecision	Publication bias	Overall certainty
Stroke or systemic embolism	4 RCTs (n = 202)	Serious¹	Not serious	Not serious	Very serious²	Undetected	⊕○○○ VERY LOW
Major bleeding	4 RCTs (n = 202)	Serious¹	Not serious	Not serious	Very serious²	Undetected	⊕○○○ VERY LOW

Explanations:

¹All trials were open-label with high/unclear risk of performance and detection bias

²Downgraded two levels due to: (a) extremely wide confidence intervals spanning both appreciable benefit and harm, and (b) optimal information size not met (total sample < 300, events < 10)