Bias magnification in ecologic studies: a methodological investigation

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Bias magnification in ecologic studies: a methodological investigation

BACKGROUND As ecologic studies are often inexpensive to conduct, consideration of the magnitude and direction of ecologic biases may be useful in both study design and sensitivity analysis of results. This paper examines three types of ecologic bias: confounding by group, effect measure modification by group, and non-differential exposure misclassification. METHODS Bias of the risk difference...

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ژورنال

عنوان ژورنال: Environmental Health

سال: 2007

ISSN: 1476-069X

DOI: 10.1186/1476-069x-6-17