Table 2.

General Quality Assessment Summary: Review Authors' Judgments for Each Study

Study	Q1	Q2	Q3	Q4	Q5	Q6	Q7	Q8	Q9	Q10	Q11	Q12	Q13	Q14	Overall score, %	Qualitya
Wu and Koo7	2	2	1	2	2	0	0	2	1	2	2	2	2	2	79	Moderate
Kwan et al.31	2	2	1	1	2	2	2	2	2	2	2	2	1	1	86	High
Ayyari et al.35	2	1	1	2	2	1	0	2	2	2	1	1	1	1	68	Moderate
Mok et al.32	2	2	1	2	2	0	0	2	2	2	1	1	1	1	68	Moderate
Stinson and Kirk40	2	2	1	1	2	0	0	2	1	2	1	1	1	1	61	Moderate
Musarezaie et al.37	2	1	1	2	2	2	0	1	1	2	1	2	1	1	68	Moderate
Babamohamadi et al.36	2	2	1	2	2	0	1	2	2	2	1	2	2	2	82	High
Wang et al.33	2	2	1	2	2	0	0	2	2	2	1	2	1	1	71	Moderate
Butts6	2	2	1	1	2	0	0	1	1	2	1	2	1	1	61	Moderate
Pramesona et al.34	2	2	1	2	0	0	0	2	2	2	2	1	2	2	71	Moderate
Ichihara et al.25	2	2	1	2	0	0	0	2	2	2	1	2	2	2	71	Moderate
Elham et al.3	2	2	1	2	0	0	0	2	2	2	1	1	1	1	61	Moderate
Alp and Yucel2	2	2	1	2	1	0	0	2	2	2	1	2	1	1	68	Moderate
Zhang et al.30	2	2	1	1	0	2	0	1	2	2	1	1	2	2	68	Moderate
Carvalho et al.38	2	2	1	1	NA	NA	NA	1	1	2	1	1	1	1	64	Moderate
Vlasblom et al.39	2	1	1	2	NA	NA	NA	1	2	2	1	1	1	1	68	Moderate

Studies were scored using the Standard Quality Assessment Criteria for Evaluating Primary Research Articles developed by the Alberta Heritage Foundation for Medical Research.²⁸ Score: yes (2 points), partial (1 point), no (0 points), or NA (not applicable). Q1, question/objective; Q2, design; Q3, method of subject/comparison group; Q4, subject characteristics; Q5, intervention and random allocation; Q6, blinding of investigators; Q7, blinding of subjects; Q8, outcome(s)/robust measurement; Q9, sample size; Q10, analytic methods; Q11, estimate of variance (e.g., confidence intervals, standard errors); Q12, controlled for confounding; Q13, results reported; Q14, conclusions supported by the results.

^a Quality of each study as low if the overall score is below 60%, moderate if the overall score is between 60% and 79%, and high if it is above 80%.