Evidence map›Paper›PMID 29624292›Full record

ArticleEnvironmental health perspectives2018

Bias Amplification in Epidemiologic Analysis of Exposure to Mixtures.

Marc G Weisskopf, Ryan M Seals, Thomas F Webster

Abstract read
In one paragraph

Article in Environmental health perspectives, 2018. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 93 papers, 4 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
93citing papers in PubMed, 4 pooled it
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

93 citing papers in PubMed, 4 syntheses or guidelines pooled it.

  1. Pooled it
  2. Pooled it
  3. Pooled it
  4. Effects of Polybrominated Diphenyl Ethers on Child Cognitive, Behavioral, and Motor Development.International journal of environmental research and public health · 2018
    Pooled it
  5. Article
  6. Article
  7. Review
  8. Workflow for Statistical Analysis of Environmental Mixtures.Environmental health perspectives · 2026
    Review
  9. Article
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  14. Review
  15. Article
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33 more citing papers are in PubMed but not listed here.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

3 authors.

Marc G WeisskopfDepartment of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
Ryan M SealsDepartment of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
Thomas F WebsterDepartment of Environmental Health, Boston University School of Public Health, Boston, Massachusetts, USA

Funding

Training CoreP42ES007381 · NIEHS · BOSTON UNIVERSITY MEDICAL CAMPUS · PI MONTI, STEFANO · 1995 to 2019
$46.1M
Translational Research Support CoreP30ES000002 · NIEHS · HARVARD UNIVERSITY (SCH OF PUBLIC HLTH) · PI SUSAN A KORRICK · 1985 to 2026
$44.6M
Early and late-life metal exposures and Alzheimer's diseaseR01ES024165 · NIEHS · HARVARD SCHOOL OF PUBLIC HEALTH · PI WEISSKOPF, MARC G · 2014 to 2019
$3.3M
Training in Neurostatistics and NeuroepidemiologyT32NS048005 · NINDS · HARVARD UNIVERSITY (SCH OF PUBLIC HLTH) · PI ONNELA, JUKKA-PEKKA · 2004 to 2018
$3.2M
Novel Analytical and Experimental Approaches for Predicting the Biological Effects of MixturesR01ES027813 · NIEHS · BOSTON UNIVERSITY MEDICAL CAMPUS · PI WEBSTER, THOMAS F · 2017 to 2021
$2.2M
Development and Testing of Response Surface Methods for Investigating the Epidemiology of Exposure to MixturesR01ES028800 · NIEHS · BOSTON UNIVERSITY MEDICAL CAMPUS · PI WEBSTER, THOMAS F · 2018 to 2021
$1.7M
Big data screening for associations between medication use and ALSR21NS099910 · NINDS · HARVARD SCHOOL OF PUBLIC HEALTH · PI WEISSKOPF, MARC G · 2017 to 2018
$399k
NIEHS NIH HHS P30 ES000002NIEHS NIH HHS P42 ES007381NIEHS NIH HHS R01 ES024165NIEHS NIH HHS R01 ES027813NIEHS NIH HHS R01 ES028800NINDS NIH HHS R21 NS099910NINDS NIH HHS T32 NS048005
6 · The paper itself

Abstract

backgroundThe analysis of health effects of exposure to mixtures is a critically important issue in human epidemiology, and increasing effort is being devoted to developing methods for this problem. A key feature of environmental mixtures is that some components can be highly correlated, raising the issues of confounding by coexposure and colinearity. A relatively unexplored topic in epidemiologic analysis of mixtures is the impact of residual confounding bias due to unmeasured or unknown variables.

objectivesThis paper examines the potential amplification of such biases when correlated exposure variables are included in regression models.

methodsWe use directed acyclic graphs (DAGs) to describe different simple scenarios involving residual confounding. We derive expressions for the expected value of the resulting bias using linear models and multiple linear regression.

resultsApproaches to the analysis of mixtures that involve regressing the outcome on several exposures simultaneously can in some cases amplify rather than reduce confounding bias. DISCUSSIONS: The problem of bias amplification can worsen with stronger correlation between mixture components or when more mixture components are included in the model.

conclusionsInvestigators must consider steps to minimize possible bias amplification in the design and analysis of epidemiologic studies of multiple correlated exposures. This may be particularly important when biomarkers of exposure are used. https://doi.org/10.1289/EHP2450.

Indexed as

BiasConfounding Factors, EpidemiologicEpidemiologic MethodsHumansLinear Models

Identifiers

PMID29624292
PMCPMC6071813

What OpenQuestion holds

Textmetadata
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Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.