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. 2020 Nov 1;74(11):907–912. doi: 10.1136/jech-2020-214117

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© Author(s) (or their employer(s)) 2020. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

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Directed acyclic graph representing our working assumptions about the causal relationships between exposure, outcomes and a simplified set of confounders.