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01-05-2009 | Commentary

Mediation and mechanism

Author: Tyler J. VanderWeele

Published in: European Journal of Epidemiology | Issue 5/2009

Abstract

The concepts of mediation and mechanism are contrasted and logical implications holding between theses two concepts are described. The concept of mediation can be formalized using counterfactual definitions of indirect effects; the concept of mechanism can be formalized within the sufficient cause framework. It is shown that both concepts can be illustrated using a single causal diagram. It is also shown that mediation implies mechanism but mechanism need not imply mediation. Discussion is given regarding how the distinction between “statistical causality” and “mechanistic causality” is blurred by recent work in causal inference concerning methods for testing for mediation and mechanism.

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Title: Mediation and mechanism
Author: Tyler J. VanderWeele
Publication date: 01-05-2009
Publisher: Springer Netherlands
Published in: European Journal of Epidemiology / Issue 5/2009
Print ISSN: 0393-2990
Electronic ISSN: 1573-7284
DOI: https://doi.org/10.1007/s10654-009-9331-1

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Mediation and mechanism

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