Table 2.

Summary of Overall Quality of Evidence of Studies Included in Each Meta-analysis Using GRADE:

Certainty Assessment
Outcome	Number of Studies	Study Design	Risk of Bias	Inconsistency	Indirectness	Imprecision	Others	Certainty
Chewing gum vs pharmacological agents	7	RCTs	Seriousa	Seriousb	Seriousc	Not serious	Not serious	⊕○○○ Very low
Chewing gum vs placebo	4	RCTs	Seriousa	Seriousd	Not serious	Seriouse	Not serious	⊕○○○ Very low
Chewing gum vs hard bite wafer	2	RCTs	Seriousa	Seriousf	Not serious	Seriouse	Not serious	⊕○○○ Very low

^aDowngraded due to unclear or absence of blinding of both patients and outcome assessors.

^bDowngraded due to high heterogeneity (P < .00001); I² = 88%.

^cDowngraded due to the inclusion of studies that reported mean pain at 24 h in females only.

^dDowngraded due to moderate level of heterogeneity; I² = 44%.

^eDowngraded due to small sample size.

^fDowngraded due to small number of studies and imprecise I².