Table 2.

Assessment of Multiple Systematic Reviews (AMSTAR) scale ratings of the 12 included systematic reviews

AMSTAR criteria	Beasley 1991[7]	Khan 2000[26]	Fergusson 2005[8]	Gunnell 2005[11]	Dubicka 2006[24]	Hammad 2006[25]	Apter 2006[20]	Bridge 2007[18]	Tauscher- Wisniewski 2007[19]	Beasley 2007[21]	Stone 2009[23]	Carpenter 2011[22]	proportion with item present	kappaa
1. Was an ‘a priori’ design provided?	Yes	No	Yes	No	Yes	No	Yes	Yes	Yes	No	Yes	Yes	8/12	0.47
2. Was there duplicate study selection and data extraction?	Yes	No	Yes	No	No	Yes	Yes	No	No	Yes	Yes	Yes	7/12	0.68
3. Was a comprehensive literature search performed?	Yes	No	Yes	No	Yes	No	No	Yes	No	No	No	No	4/12	0.63
4. Was the status of publication used as an inclusion criterion?	Yes	No	No	Yes	Yes	Yes	Yes	Yes	No	No	Yes	Yes	8/12	0.33
5. Was a list of studies provided?	No	No	No	No	No	Yes	No	No	No	No	No	Yes	2/12	0.75
6. Were the characteristics of the included studies provided?	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes	Yes	11/12	0.63
7. Was the scientific quality of the included studies assessed and documented?	No	No	No	No	Yes	Yes	No	Yes	No	No	No	No	3/12	0.47
8. Was the scientific quality of the included studies used appropriately in formulating conclusions?	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes	No	10/12	0.56
9. Were the methods used to combine the findings of studies appropriate?	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes	11/12	0.25
10. Was the likelihood of publication bias assessed?	No	No	No	No	No	No	No	Yes	No	No	No	No	1/12	0.63
11. Was the conflict of interest stated?	No	No	Yes	Yes	Yes	No	No	Yes	No	No	Yes	Yes	6/12	0.67
Total score (out of 11)	7	3	7	5	8	7	6	9	2	3	7	7	---	0.86b
Overall methodological quality (L=low,M=moderate,H=high)	M	L	M	M	M	M	M	H	L	L	M	M	---	---

^a Kappa values for inter-rater reliability of the two independent coders who assessed each of the 11 items for the 12 reviews

^b Intraclass correlation coefficient (ICC) assessing the inter-rater reliability of the two independent raters of the total quality score for the 12 reviews