Let the question determine the methods: descriptive epidemiology done right

Summary

What does it mean to control for confounding, and when do we actually need to do it? To answer this, we need a well-defined research question, driven by the goal of the study. For descriptive goals, we explain that confounding adjustment is often not just unnecessary but can be harmful.

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Acknowledgements

This commentary arose from discussion on #epitwitter. The authors would like to thank everyone who contributed to that conversation.

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E.M. had the initial idea for the commentary. S.C. wrote the first draft with notes from E.M. S.C. and E.M. revised and approved the final version.

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Correspondence to Sara Conroy.

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Conroy, S., Murray, E.J. Let the question determine the methods: descriptive epidemiology done right. Br J Cancer (2020). https://doi.org/10.1038/s41416-020-1019-z

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