Modelling complex mixtures in epidemiologic analysis: Additive versus relative measures for differential effectiveness

Ghassan Hamra, Richard MacLehose, David Richardson, Stephen Bertke, Robert D. Daniels

Research output: Contribution to journalArticle

Abstract

Objectives: Mixed exposures are often combined into single exposure measures using weighting factors. This occurs for many complex mixtures in environmental and occupational epidemiology including multiple congeners, air pollutants and unique forms of ionising radiation, among others. Methods: The weights used for combining exposures are most often determined from experimental animal and cellular research. However, evidence from observational research is necessary to support their use in risk analyses, since results from experimental research do not directly translate to observational epidemiology. Results: Using simulated data, we show that ratio-based relative weights cannot be reliably estimated from observational research. As a solution to this problem, we propose an approach for estimating differences in effectiveness of distinct exposures based on their excess effectiveness compared with a reference exposure. Conclusions: This alternative is easy to calculate and provides reliable estimates of differences in effectiveness of distinct exposures. This is important to regulatory bodies using relative measures for policy decisions, as well as practicing epidemiologists conducting risk analyses.

Original languageEnglish (US)
Pages (from-to)141-146
Number of pages6
JournalOccupational and Environmental Medicine
Volume71
Issue number2
DOIs
StatePublished - Feb 1 2014
Externally publishedYes

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Complex Mixtures
Epidemiology
Research
Weights and Measures
Air Pollutants
Ionizing Radiation

ASJC Scopus subject areas

  • Public Health, Environmental and Occupational Health

Cite this

Modelling complex mixtures in epidemiologic analysis : Additive versus relative measures for differential effectiveness. / Hamra, Ghassan; MacLehose, Richard; Richardson, David; Bertke, Stephen; Daniels, Robert D.

In: Occupational and Environmental Medicine, Vol. 71, No. 2, 01.02.2014, p. 141-146.

Research output: Contribution to journalArticle

Hamra, Ghassan ; MacLehose, Richard ; Richardson, David ; Bertke, Stephen ; Daniels, Robert D. / Modelling complex mixtures in epidemiologic analysis : Additive versus relative measures for differential effectiveness. In: Occupational and Environmental Medicine. 2014 ; Vol. 71, No. 2. pp. 141-146.
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