Table 3: Methodological quality scores.
Washburn et al. [43]Wells et al. [44]Zhang et al. [45]Montazeri et al. [46]Wu
et al. [47]		Wen et al. [48]Margolin et al. [49]Zeng et al. [50]Mu
et al. [51]		Bearn et al. [52]
(1) Was the study described as randomized? V V V V V V V V V V
(2) Was the randomization scheme described and appropriate? x V x V x V x x V V
(3) Was the study described as double-blind? x x x x x x x x x x
(4) Was the method of double-blinding appropriate? x x x x x x x x x x
(5) Was there a description of dropouts and withdrawals? x V x x x x x x x V
Results1312121123
V: yes = 1; x: no = 0; low quality, 0–2; high quality, 3–5.