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. 2017 Dec 8;96(49):e8976. doi: 10.1097/MD.0000000000008976

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Copyright © 2017 the Author(s). Published by Wolters Kluwer Health, Inc.

This is an open access article distributed under the Creative Commons Attribution-NoDerivatives License 4.0, which allows for redistribution, commercial and non-commercial, as long as it is passed along unchanged and in whole, with credit to the author. http://creativecommons.org/licenses/by-nd/4.0

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Table 2.

Assessment of risk of bias.

3.3.