Paper – Systematic Reviewlution

Keywords	• Grey literature • General medical • Publication bias
Problem(s)	• Grey literature excluded • Poor consideration of publication bias
Article Type	Empirical
Article Subtype	Cross-sectional survey/Methodological systematic review
First Author Country	Canada
Aim	To assess whether a sample of systematic reviews searched for unpublished data, whether it was included in the analysis and whether publication bias was assessed.
Level of Investigation	Descriptive
Summary of Findings	36% of reviews did not describe an attempt to search for unpublished studies. Of those that did, 40% included unpublished data in analyses. 33% of reviews assessed publication bias and 40% of these reviews revealed evidence of publication bias.
Number of systematic reviews included	203
Number of eligible systematic reviews assessed	204
Treatment impacted	No
Treatment impacted description
Interpretation impacted	Not Applicable
Interpretation impacted description

Does the article have a publicly available protocol?	No
Did the review team include both methodological and clinical experts?	Not Applicable
Sampling strategy for obtaining the systematic reviews under assessment	Consecutive
Was the sample size of systematic reviews subject to any formal sample size or power calculation?	No
Were any or all of the study selection and data extraction performed in duplicate?	Yes
Were any statistical adjustments made to correct for confounding?	Not Applicable
Are the methods of the article described in enough detail to replicate the study?	Yes