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Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
Consort diagram of trial inclusion and exclusion, and categorization. * Other reasons include having trials still listed as phase 2 on clinicaltrials.gov (3), Extension study of an included trial (1), phase 4 (1), anticipated start date 1987 (1), and a supportive trial (1).