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PubMed · 10750060

Sample size to test for interaction between a specific exposure and a second risk factor in a pair-matched case-control study.

P Qiu·M L Moeschberger·G E Cooke·P J Goldschmidt-Clermont
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Abstract

We discuss a sample size calculation for a pair-matched case-control study to test for interaction between a specific exposure and a second risk factor. The second risk factor could be either binary or continuous. An algorithm for the calculation of sample size is suggested which is based on a logistic regression model that relates the logarithm of the disease-exposure odds ratio to the second risk factor. This problem is motivated by a study comparing the prevalence of GP-IIIa Pl(A2) polymorphism (the exposure) in individuals with and without myocardial infarction (case-control). One of the hypotheses in this study is whether or not there is an interaction between the prevalence of GP-IIIa Pl(A2) polymorphism and a second risk factor such as smoking status and homocysteine level. We introduce the algorithm in detail with several numerical examples.

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AlgorithmsCase-Control StudiesData Interpretation, StatisticalHomocysteineHumansMyocardial InfarctionPolymorphism, GeneticRisk FactorsSample SizeSmokingJournal Article

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P Qiu, M L Moeschberger, G E Cooke, P J Goldschmidt-Clermont. 2000-04-15. Sample size to test for interaction between a specific exposure and a second risk factor in a pair-matched case-control study.. https://doi.org/10.1002/(sici)1097-0258(20000415)19%3A7%3C923%3A%3Aaid-sim341%3E3.0.co%3B2-o

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