Search results
- The key distinction between interaction and effect modification is that with effect modification, interest is in the effect of one single exposure on an outcome and this relationship does not have to be causal, whereas with interaction interest is in the causal effect of two exposures on an outcome.
encepp.europa.eu › encepp-toolkit › methodological-guideChapter 7: Effect modification and interaction - European Union
People also ask
What is the difference between interaction and effect modification?
What happens when effect modification is present?
What is effect modification in epidemiology?
Is effect modification a covariable?
When effect modification (also called interaction) is present, there will be different results for different levels of the third variable (also called a covariable). For example, if we do a cohort study on amount of sleep and GPA among Oregon State University (OSU) students over the course of one term, we might collect these data:
Effect modification is similar to statistical interaction, but in epidemiology, effect modification is related to the biology of disease, not just a data observation. In the previous example, we saw both stratum-specific estimates of the odds ratio went to one side of the crude odds ratio.
Interaction is defined in terms of the effects of 2 interventions whereas effect modification is defined in terms of the effect of one intervention varying across strata of a second variable. Effect modification can be present with no interaction; interaction can be present with no effect modification.
Abstract: In this tutorial, we provide a broad introduction to the topic of interaction between the effects of exposures. We discuss interaction on both additive and multiplicative scales using risks, and we discuss their relation to statistical models (e.g. linear, log-linear, and logistic models).
Effect modification is similar to statistical interaction, but in epidemiology, effect modification is related to the biology of disease, not just a data observation. In the hypertension example, we saw both stratum-specific estimates of the odds ratio went to one side of the crude odds ratio.
The key distinction between interaction and effect modification is that with effect modification, interest is in the effect of one single exposure on an outcome and this relationship does not have to be causal, whereas with interaction interest is in the causal effect of two exposures on an outcome.
The notions of effect modification, interaction and media-tion represent conceptually different, although potentially interdependent notions. These subtle different notions address different research aims, which are related to different aspects of an exposure–outcome relationship (Box 1).
