Table 3.

Quality assessment through QualSyst.

Item No.	Friese et al. [35]	Yusainy and Lawrence [36]	Wang et al. [37]	Stocker et al. [16]	Axelsen et al. [38]	Shaabani et al. [39]	Zhu et al. [40]	Coimbra et al. [41]
I	2	2	2	2	2	2	2	2
II	2	2	2	2	2	2	2	2
III	2	2	2	2	2	2	2	2
IV	2	2	2	2	2	2	2	2
V	0	2	2	2	2	2	2	2
VI	0	0	0	2	0	1	0	0
VII	0	0	0	0	1	2	2	2
VIII	2	2	2	2	2	2	2	2
IX	2	2	2	2	2	2	1	2
X	2	1	2	1	2	2	2	2
XI	2	2	2	2	2	2	2	2
XII	0	0	0	0	0	0	0	0
XIII	2	2	2	2	2	2	2	2
XIV	2	2	2	2	2	2	2	2
Rating	Moderate	Strong	Strong	Strong	Strong	Strong	Strong	Strong

Note. 2 indicates yes, 1 indicates partial, 0 indicates no, I question described, II appropriate study design, III appropriate subject selection, IV characteristics described, V random allocation, VI researcher blinded, VII subjects blinded, VIII outcomes measure well defined and robust to bias, IX sample size appropriate, X analytic methods well described, XI estimate of variance reported, XII controlled for confounding, XIII results reported in detail, and XIV conclusion supported by results.