Fitting Binomial, Quasi – Binomial, Poisson and Quasi - Poisson Models in Analyzing In Vivo Micronucleus Assay Data


  • Shiena Zaira B. Canlas Central Luzon State University
  • John Closter F. Olivo Central Luzon State University



binomial, Poisson, quasi-Binomial, quasi-Poisson, over-dispersion


Micronucleus assay is an important analysis for testing the genotoxicity of a compound thus, a careful analysis should be done. The main focus of this study was to perform the recommendations of Hothorn and Gerhard (2009) on analyzing the number and proportion of micronucleus polychromatic erythrocytes for a given number of polychromatic erythrocytes. The compound TO1 was evaluated using the Binomial, Poisson, quasi-Binomial and quasi-Poisson models. Results showed that most doses of TO1 had no significant effect on the proportion of micronucleus. The result of quasi- Binomial and quasi-Poisson model revealed that most of the inferences agree with the results of the traditional models. However, some inferences can lead to a false positive decision if over-dispersion was not taken into account. The analysis also showed that TO1 was found to be a negative compound.

Author Biographies

Shiena Zaira B. Canlas, Central Luzon State University

Department of Statistics, College of Arts and Sciences

John Closter F. Olivo, Central Luzon State University

Department of Statistics, College of Arts and Sciences


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Hothorn LA and Gerhard, D. 2009. Statistical evaluation of the In Vivo Micronucleus Assay. Arch Toxicol. 83:625–634.