Table 3 Quality assessment of the studies included in the meta-analysis
Study | Sample size calculation | Random allocation to treatment | Husbandry conditions | Blinded assessment of outcomes | Compliance with animal welfare regulations | Conflicts of interest disclosed | Peer-reviewed publication | Quality score |
|---|---|---|---|---|---|---|---|---|
Hsu PY 2016 [6] | N | Y | Y | N | Y | N | Y | 4 |
Jiang L 2017 [31] | N | Y | Y | Y | Y | Y | Y | 6 |
Kim KH 2002 [29] | N | N | Y | N | N | N | N | 1 |
Kuroda S 2003 [30] | N | N | N | N | Y | N | Y | 2 |
Li CL 2014 [12] | N | Y | Y | N | Y | Y | Y | 5 |
Liu H 2015 [19] | N | Y | N | N | N | N | N | 1 |
Liu XL 2015 [32] | N | Y | N | N | Y | N | Y | 3 |
Liu Z 2015 [33] | N | Y | N | N | Y | N | Y | 3 |
Liu ZS 2015 [34] | N | Y | Y | N | Y | N | Y | 4 |
Mavropoulos A 2014 [35] | N | N | N | N | Y | Y | Y | 3 |
Moriya Y 1998 [15] | N | Y | Y | N | Y | N | Y | 4 |
Patullo IM 2009 [36] | N | Y | Y | Y | Y | N | Y | 5 |
Sun W 2014 [40] | N | Y | N | N | Y | Y | Y | 4 |
Tanaka M 1998 [37] | N | Y | Y | N | N | N | Y | 3 |
Tanaka M 2003 [38] | N | Y | Y | N | Y | N | Y | 4 |
Yang J 2003 [39] | N | N | Y | N | N | N | Y | 2 |