Table 3.

Systematic Review/Meta-Analysis (Modified Scottish Intercollegiate Guideline Network—Checklist)

	Item	Yes/noa
1	Research question clearly defined, and eligibility criteria listed.
2	Comprehensive literature search conducted.
3	At least two people selected studies.
4	At least two people extracted data.
5	Status of publication not used as an inclusion criterion.
6	Excluded studies listed.
7	Relevant characteristics of included studies provided.
8	Quality of included studies assessed and reported.
9	At least two people assessed quality of included studies.
10	Appropriate methods used to combine individual study results.
11	Likelihood of publication bias assessed appropriately.
12	Conflicts of interest declared.
	Total scoreb

^a Rating: “Yes” = 1; “No” or unable to tell from the article = 0.

^b Scoring—sum of items as follows: 10–12 = high quality, low risk of bias; 6–9 = acceptable quality, moderate risk of bias; <6 = low quality, high risk of bias.