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. 2019 May 19;9(5):e022912. doi: 10.1136/bmjopen-2018-022912

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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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Effect size: industry sponsored and/OR author conflict of interest (COI) versus non-industry-sponsored and no author COI studies, risk ratio.