Estimating Variance Functions in Developmental Toxicity Studies

The presence of intralitter correlation is a well known issue for analysis of the developmental toxicology data. The intralitter correlation coefficients observed in developmental toxicology data are generally different across dose groups. In this paper we use a generalized estimating equation procedure to model jointly the mean parameters and the intralitter correlation coefficients as functions of dose levels. Our procedure is similar to that used by Prentice and Zhao (1991, Biometrics 47, 825-839) for estimating the mean and variance parameters.

Related Organizations

University of Mississippi
United States

Keywords

Analysis of Variance, Biometry, Drug-Related Side Effects and Adverse Reactions, Litter Size, 2,4,5-Trichlorophenoxyacetic Acid, Abnormalities, Drug-Induced, Applications of statistics to biology and medical sciences; meta analysis, Cleft Palate, Embryonic and Fetal Development, Mice, Teratogens, Pregnancy, Animals, Female, Fetal Death

Impact byBIP!

	selected citations These citations are derived from selected sources. This is an alternative to the "Influence" indicator, which also reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).	18
	popularity This indicator reflects the "current" impact/attention (the "hype") of an article in the research community at large, based on the underlying citation network.	Average
	influence This indicator reflects the overall/total impact of an article in the research community at large, based on the underlying citation network (diachronically).	Top 10%
	impulse This indicator reflects the initial momentum of an article directly after its publication, based on the underlying citation network.	Average