Abstract:
:In epidemiological studies we often want to learn about the direct effect of an exposure on an outcome, i.e. the effect that is not relayed by a specific intermediate variable. In the literature, there are two common definitions of direct effects; controlled and natural. When the intermediate variable and the outcome have common causes, neither the controlled nor the natural direct effect is identified. Cai et al. (Biometrics 2007; 64(3):695-701) derived bounds for the controlled direct effect under a set of hierarchical assumptions. In this paper we derive bounds on the natural direct effect under the same assumptions.
journal_name
Stat Medjournal_title
Statistics in medicineauthors
Sjölander Adoi
10.1002/sim.3493subject
Has Abstractpub_date
2009-02-15 00:00:00pages
558-71issue
4eissn
0277-6715issn
1097-0258journal_volume
28pub_type
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