Table 2. Risk of Bias in Studies.

Source	Intention-to-treat analysis	Allocation concealment	Blinding	Lost to follow up
Katafuchi R 2008 [28]	No	Unclear	Unclear	No lost to follow-up
Koike M 2008[29]	Yes	Unsealed envelops	Yes: patients and caregivers	No lost to follow-up
Pozzi C 2004[30]	Yes	Yes	Unclear	No lost to follow-up
Moriyama T 2004[31]	Yes	Unclear	No	No lost to follow-up
Katafuchi R 2003[32]	No	Yes	No	Lost to follow-up: 13 patients
Shoji T 2000[33]	No	Yes	No	Lost to follow-up:2 patients
K.N.Lai 1986[34]	No	Unclear	No	No lost to follow-up
Kobayashi Y 1996[35]	No	Inadequate	No	Lost to follow-up:44 patients
Welch TR 1992[36]	Unclear	Yes	Yes: patients and investigators	Lost to follow-up:3 patients
Kobayashi Y 1988[37]	No	Unclear	Unclear	No lost to follow-up
Julian BA 1993[38]	No	Yes	Unclear	Lost to follow-up:2 patients
Uzu T 2003[39]	No	No	Unclear	No lost to follow-up
Manno C[21]	Yes	Yes	No	Lost to follow-up: 6 patients
Lv J[22]	Yes	Yes	No	Lost to follow-up: 3 patients
Locatelli F 2001[40]	Yes	Unclear	Unclear	Lost to follow-up: 12 patients