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. 2021 Feb 12;38(3):1447–1469. doi: 10.1007/s12325-021-01628-7

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© The Author(s), under exclusive licence to Springer Healthcare Ltd. part of Springer Nature 2021

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Fig. 1 — Study flow diagram with exclusion criteria. Of the 1138 studies initially identified through the database search, only nine were eventually included in the qualitative analysis