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. 2022 Nov 2;21:15347354221133561. doi: 10.1177/15347354221133561

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© The Author(s) 2022

This article is distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 License (https://creativecommons.org/licenses/by-nc/4.0/) which permits non-commercial use, reproduction and distribution of the work without further permission provided the original work is attributed as specified on the SAGE and Open Access page (https://us.sagepub.com/en-us/nam/open-access-at-sage).

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Figure 1. — Flow-chart of literature search. *Reasons for exclusions: Treatment with fME or mix including fME (14 studies), double publication (7×), survival not as outcome (7×), no control group (16×), and insufficient information (3×).