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PubMed · 2049507

Generalized variance component models for clustered categorical response variables.

M E Miller·J R Landis
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Abstract

A generalized variance component model is proposed for the analysis of a categorical response variable with extra-multinomial variation. Categorical data obtained from research designs such as randomized multicenter clinical trials or complex sample surveys with clustering frequently exhibit extra-variation resulting from intracluster correlation. General correlation patterns are accounted for by utilizing a mixed-effects modelling approach, estimating the cluster variance components through the method of moments and modelling functions of the observed proportions through the use of estimating equations. A flexible set of assumptions characterizing the underlying covariance structure for the proportions can be accommodated. The importance of accounting for extra-variation when performing hypothesis tests is highlighted with an application to data from a multi-investigator clinical trial.

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M E Miller, J R Landis. 1991. Generalized variance component models for clustered categorical response variables.. https://pubmed.ncbi.nlm.nih.gov/2049507/

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