Consistency in statistical analyses of preclinical studies is a request from authorities worldwide because it facilitates the evaluation and comparison of similar studies. The goal of this paper is to describe mixed-effect analysis of variance models broadly applicable to the analysis of continuous responses from toxicity and safety pharmacology studies. Traditional models are discussed together with more complex models including the split-plot model and related models for repeated measurements. The model fitting process ranges from the choice of model to the final check of model assumptions which we exemplify using case studies analyzed by the SAS® procedure.
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