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Investigating Heterogeneity of Effects and Associations Using Interaction Terms




Effect heterogeneity, the variability of an association or exposure across subgroups, usually warrants further investigation. The aim of this deeper analysis is to identify effect modifiers (or moderators) and quantify their relationship with the exposure. We explain why it is better to harness interaction effects within a single analytic model than to use separate models to analyse each subgroup. Using examples, we demonstrate a practical approach to modelling and interpretation with interaction terms from various measurement scales (categorical by categorical; categorical by continuous; and continuous by continuous).

Acceptance Date Sep 15, 2017
Publication Date Jan 1, 2018
Journal Journal of Clinical Epidemiology
Print ISSN 0895-4356
Publisher Elsevier
Pages 79-83
Keywords interaction terms, effect heterogeneity, effect modifiers, split-sample
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