A nested approach to evaluating dose-response and trend.

J S Witte; S Greenland

doi:10.1016/s1047-2797(96)00159-7

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A nested approach to evaluating dose-response and trend.

J S Witte·S Greenland

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Abstract

PURPOSE: Conventional dose-response and trend analysis fits either a linear or categorical logistic model and tests the resulting coefficients. These analyses, however, are based on implausible assumptions. METHODS: We present an alternative approach that uses likelihood ratio tests to compare nested regression models and determine when a model is rich enough to capture the data trends. RESULTS: For illustration, we apply this approach to data on diet and colorectal polyps. CONCLUSIONS: Comparison of linear and quadratic spline logistic models indicates that the conventional approach of using only a linear logistic model would not appropriately describe the association between intake of fruits and vegetables and colorectal polyps in our data. Graphical checking further supports this conclusion.

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Case-Control Studies Colonic Polyps Dietary Fiber Epidemiologic Methods Fruit Humans Logistic Models Research Design Vegetables Journal Article Research Support, U.S. Gov't, P.H.S.

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J S Witte, S Greenland. 1997. A nested approach to evaluating dose-response and trend.. https://doi.org/10.1016/s1047-2797(96)00159-7

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