Study Random
sequence
generation 		Allocation
concealment 		Blinding of
outcome
assessment 		Incomplete
outcome
data 		Selective
reporting 		Other
sources of
bias
Kim et al. [45] + + + + + +
Coomes et al. [46] ? ? + + + +
Huh et al. [47] + + + + + +
Jain et al. [48] ? + + + + +
Saulacic et al. [49] + + + ? + +
Pelegrine et al. [50] ? ? + + + +
Geurs et al. [51] + + + + + +
Wallace et al. [52] ? ? + + + +
Mayer et al. [53] + + + + + +
Heberer et al. [54] ? ? + + + +
Kaigler et al. [55] + + + + + +

+ = low risk; ? = unclear risk; - = high risk.