Cited by 494Statistical Methods in EpidemiologyAdvanced Causal Inference TechniquesMeta-analysis and systematic reviews

Invited commentary: ecologic studies—biases, misconceptions, and counterexamples

Greenland, Sander, Robins, James·1994·American Journal of Epidemiology

Abstract

Many authors have pointed out that relative-risk estimates derived from ecologic data are vulnerable to biases not found in estimates derived from individual-level data. Nevertheless, biases in ecologic studies still are often dealt with in the same manner as biases in other observational studies, and so are not given adequate treatment. This commentary reviews and illustrates some of the more recent findings about bias in ecologic estimates. Special attention is given to problems of ecologic confounder control when individual risks follow a nonlinear model, and to misconceptions about ecologic bias that have appeared in the literature.

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Crossref · 10.1093/oxfordjournals.aje.a117069

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  • Ecological studies cannot establish that the exposed individual is the same as the diagnosed individual and cannot account for individual-level confounding.

    “In aggregate outcome data, it cannot be known that the individual experiencing the exposure is the same individual within the group that had an autism diagnosis. Furthermore, it is not possible to account for individual-level confounding influences in this type of design”

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Authors
Greenland, S., & Robins, J.
Affiliations
  • University of California, Los Angeles (US)
  • Harvard University (US)
Corresponding author
Greenland, Sander
Venue
American Journal of Epidemiology
Published
1994-04-15
Volume
139
Issue
8
Pages
747-760
ISSN
  • 0002-9262 (ISSN-L)
  • 1476-6256
OpenAlex
W2131305454
Cited by
494
References
21
Citations by year
2026: 22 · 2025: 7 · 2024: 8 · 2023: 10 · 2022: 10 · 2021: 19 · 2020: 14 · 2019: 6 · 2018: 7 · 2017: 8 · 2016: 15 · 2015: 15 · 2014: 19 · 2013: 16 · 2012: 11
Type
journal article
Language
en
Open access
closed
Locations
  • American Journal of Epidemiology (publishedVersion)
  • PubMed (publishedVersion)
Funders
  • National Institutes of Health (5k04es000180-03)
  • National Institute of Allergy and Infectious Diseases (R01AI032475)
  • National Institute of Environmental Health Sciences (P30ES000002, K04-ES00180)
Topics
  • Physical Sciences › Mathematics › Statistics and Probability › Statistical Methods in Epidemiology
  • Physical Sciences › Mathematics › Statistics and Probability › Advanced Causal Inference Techniques
  • Social Sciences › Decision Sciences › Statistics, Probability and Uncertainty › Meta-analysis and systematic reviews
Keywords
ecological study, relative risk estimation, confounder control, microdata, bias in observational studies
MeSH terms
Ecology, Epidemiologic Methods, Humans, Regression Analysis, Risk, Models, Statistical, Bias, Confounding Factors, Epidemiologic

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