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. 2015 Apr 14;13:82. doi: 10.1186/s12916-015-0317-4

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© Helfer et al.; licensee BioMed Central. 2015

This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.

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Results of the primary analysis. Percentage of previous meta-analyses and systematic reviews that were cited, described, and discussed by the recent meta-analyses.