Table 4. Assessment of risk of bias.

Study	Random sequence generation	Allocation concealment	Blinding of participants	Blinding of outcome assessment	Incomplete outcome data	Selective reporting	Other bias
Atia et al. [9]	+	+	_	+	+	+	+
Joshi et al. [12]	?	_	_	?	+	+	+
Romesh et al. [13]	_	?	_	+	+	?	+
Dong-Seok et al. [14]	?	_	_	+	+	+	+
Darwish et al. [15]	+	+	_	+	+	+	+
Beneytout et al. [16]	+	+	_	?	+	?	+
Ghoderao et al. [17]	+	+	_	+	+	+	+
Soni et al. [18]	_	+	_	?	+	+	_
Tony et al. [19]	+	+	_	+	+	+	+
Parthasarathy et al. [20]	+	+	_	_	+	?	?
Abdelhamid et al. [21]	+	+	_	+	+	+	+
Bhandari et al. [22]	_	+	?	+	+	_	_