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Common referent versus shifting referent methods when using case-control data to examine patterns of incidence across multiple exposure variables.

Garth H Rauscher·Charles Poole
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Abstract

PURPOSE: In case-control studies, when odds ratios estimate rate ratios or risk ratios, trends in odds ratios can reflect trends in incidence in the underlying population. METHODS AND RESULTS: In this report, we use an empirical example and hypothetical data to compare two methods ("common referent" and "shifting referent") for calculating odds ratios from case-control data across multiple exposure variables. With common referent methods, a single independent variable is constructed from the joint distribution of all exposure variables. With shifting referent methods, each stratum-specific trend has its own referent. CONCLUSIONS: Using examples involving a single ordinal "trend" variable and a dichotomous "stratification" variable, we show that common referent odds ratios will reflect the pattern of incidence in the underlying population, whereas odds ratios calculated using shifting referent methods will not.

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Case-Control StudiesIncidenceModels, StatisticalOdds RatioComparative StudyJournal ArticleResearch Support, N.I.H., ExtramuralResearch Support, Non-U.S. Gov't

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Garth H Rauscher, Charles Poole. 2006-08-08. Common referent versus shifting referent methods when using case-control data to examine patterns of incidence across multiple exposure variables.. https://doi.org/10.1016/j.annepidem.2006.04.011

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