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The DOI matches its Crossref record; 12 of the 12 references it cites were found in a registry or an index.

A definition of causal effect for epidemiological research

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Hernán, M A·2004·Journal of Epidemiology and Community Health

Abstract

Estimating the causal effect of some exposure on some outcome is the goal of many epidemiological studies. This article reviews a formal definition of causal effect for such studies. For simplicity, the main description is restricted to dichotomous variables and assumes that no random error attributable to sampling variability exists. The appendix provides a discussion of sampling variability and a generalisation of this causal theory. The difference between association and causation is described—the redundant expression “causal effect” is used throughout the article to avoid confusion with a common use of “effect” meaning simply statistical association—and shows why, in theory, randomisation allows the estimation of causal effects without further assumptions. The article concludes with a discussion on the limitations of randomised studies. These limitations are the reason why methods for causal inference from observational data are needed.

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Metadata

Authors
Hernán, M. A.
Venue
Journal of Epidemiology and Community Health
Publisher
BMJ
Published
2004-03-16
Volume
58
Issue
4
Pages
265-271
ISSN
  • 0141-7681 (ISSN-L)
  • 0143-005X
  • 1470-2738
OpenAlex
W2150300473
Cited by
462
References
12
FWCI
5.25
Type
journal article
Language
en
Open access
bronze

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CoChat. (2026). Citation check: A definition of causal effect for epidemiological research. https://app.cochat.ai/papers/10.1136/jech.2002.006361
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Hernán, M. A. (2004). A definition of causal effect for epidemiological research. Journal of Epidemiology and Community Health. https://doi.org/10.1136/jech.2002.006361

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Bibliographic data: Semantic Scholar, OpenAlex, Crossref.

Contains information from the Semantic Scholar Academic Graph Datasets, made available under the ODC Attribution License (ODC-BY 1.0).

Semantic Scholar’s data is described in: Kinney, R., et al. (2023). The Semantic Scholar Open Data Platform. arXiv:2301.10140.