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. 2020 Jan 21;46(3):383–400. doi: 10.1007/s00134-019-05872-y

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© The Author(s) 2020

Open AccessThis article is distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 International License (http://creativecommons.org/licenses/by-nc/4.0/), which permits any noncommercial use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

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Fig. 2 — Flow diagram. Papers identified in databases, title/abstract screened, read full text, and included in the synthesis. Reasons for exclusion are listed