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. 2021 Jun 8;11(6):e048109. doi: 10.1136/bmjopen-2020-048109

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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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Flow diagram of participant identification for the study cohort. *Non-pharmacy sites included general practices, university clinics, community clinics and local government clinics. SMS, short message service.