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. 2019 Feb 27;4(1):e001258. doi: 10.1136/bmjgh-2018-001258

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© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

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Geographic source of data for included publications. ECA, Europe/Central Asia region; LAC, Latin America/Caribbean region; MENA, Middle East/North Africa region; SSA, sub-Saharan Africa region.