Table 2.

GRADE assessment results

Comparison	Outcomes	Risk of bias	Inconsistency	Indirectness	Imprecision	Publication of bias	GRADE
Vs. no-scalp block	Very Early	Serious	Severe	No at all	No	Presence	Very low
	Early	Serious	Some	No at all	Some	Presence	Very Low
	Intermediate	Serious	Some	No at all	No	Presence	Low
	Late	Serious	No	No at all	No	Presence	Low
	Very Late	Serious	Some	No at all	No	Presence	Very Low
Vs. placebo	Very Early	Serious	Severe	No at all	No	Presence	Very low
	Early	Serious	No	No at all	No	Presence	Low
	Intermediate	Serious	No	No at all	Some	Presence	Low
	Late	Serious	No	No at all	Some	Presence	Low
	Very Late	Serious	Some	No at all	Some	Presence	Very low
Vs. no-scalp block	Opioid consumption	Serious	Some	No at all	Some	Presence	Very low
Vs. placebo	Opioid consumption	Serious	Severe	No at all	Some	Presence	Very low