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. 2023 Oct 5;3:132. doi: 10.1038/s43856-023-00358-x

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© The Author(s) 2023

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Fig. 2 — The proportion of studies (n = 70) included in the systematic review by clinical trial design and analysis type (primary trial results, extension study of a randomized controlled trial [RCT], secondary analysis of an RCT, or person-reported outcome [PRO] studies).