Table 1.

Quality analysis of included trials

Study	Randomization method	Allocation concealment	Blinding	Withdrawals	Jadad score
Byun et al[20]	Not mentioned	Unclear	Double-blind	Not mentioned	3
Lee et al[21]	Computer-generated	Adequate	Double-blind	Not mentioned	6
Corte et al[10]	Computer-generated	Adequate	Double-blind	Described	7
de Brouwer et al[15]	Not mentioned	Unclear	Double-blind	Described	4
Rondonotti et al[16]	Computer-generated	Adequate	Double-blind	Described	7