Table 3. Magnitude of the influence (in percentage) of different levels of risk of bias on the treatment effect estimates (only comparisons with at least 5 studies in each ROB group).

Study	Treatments	Domains	Domains comparison	Outcome measure	Effect	P Value
Yaacob et al. 2014	All powered toothbrushes versus manual toothbrushes	Sequence generation and sequence generation or blinding of outcome assessment	Unclear versus low ROB	Plaque scores at 1 to 3 months at all sites	35.00% higher in unclear ROB	0.535
Yaacob et al. 2014	All powered toothbrushes versus manual toothbrushes	Allocation concealment and allocation concealment or blinding of outcome assessment	Unclear versus low ROB	Plaque scores at 1 to 3 months at all sites	142.00% higher in unclear ROB	0.405
Yaacob et al. 2014	All powered toothbrushes versus manual toothbrushes	Sequence generation and sequence generation or blinding of outcome assessment	Unclear versus low ROB	Löe and Silness index	21.00% higher in unclear ROB	0.846
Yaacob et al. 2014	All powered toothbrushes versus manual toothbrushes	Allocation concealment and allocation concealment or blinding of outcome assessment	Unclear versus low ROB	Löe and Silness index	39.00% higher in unclear ROB	0.459
Yaacob et al. 2014	All powered toothbrushes versus manual toothbrushes	Blinding of outcome assessment	Unclear versus low ROB	Löe and Silness index	131.00% higher in unclear ROB	0.053
Yaacob et al. 2014	Rotation oscillation powered toothbrushes versus manual toothbrushes	Sequence generation and sequence generation or blinding of outcome assessment	Unclear versus low ROB	Plaque scores at 1 to 3 months at all sites	24.00% higher in unclear ROB	0.471
Yaacob et al. 2014	Rotation oscillation powered toothbrushes versus manual toothbrushes	Sequence generation and sequence generation or blinding of outcome assessment	Unclear versus low ROB	Gingival scores at 1 to 3 months at all sites	193.00% higher in unclear ROB	0.069