Table 2.

Quality assessments of the studies included

Study	Random-sequence generation	Allocation concealment	Blinding of participants and personnel	Blinding of outcome assessment	Incomplete outcome data	Selective reporting	Other bias
Block et al14	Unclear	Unclear	Low	Unclear	Low	Low	Low
Midgren et al16	Unclear	Unclear	Low	Unclear	Low	Low	Low
Stege et al13	Low	Unclear	Low	Unclear	Low	Low	Low
Timms et al15	Unclear	Unclear	Low	Unclear	Low	Low	Low
sSteens et al17	Unclear	Unclear	Low	Unclear	Low	Low	Low