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. 2021 Oct 12;11(10):e052668. doi: 10.1136/bmjopen-2021-052668

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© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

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Vietnam, red S shape, is located in Southeast Asia. Ho Chi Minh City, enlarging circle, is located in southern Vietnam.