Standard Article

Animal Screening Systems

  1. Joseph K. Haseman

Published Online: 15 JUL 2005

DOI: 10.1002/0470011815.b2a06001

Encyclopedia of Biostatistics

Encyclopedia of Biostatistics

How to Cite

Haseman, J. K. 2005. Animal Screening Systems. Encyclopedia of Biostatistics. 1.

Author Information

  1. National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA

Publication History

  1. Published Online: 15 JUL 2005


Animal screening systems are experimental protocols designed primarily to screen substances in laboratory animals for possible adverse effects in humans. These experiments include long-term rodent toxicity/carcinogenicity bioassays and shorter duration studies that focus on reproductive and developmental toxicology endpoints. These experiments are the first step of a broader risk assessment process to determine the magnitude of human risk associated with exposure to a test substance. Statistical issues that arise in these studies include (i) selection of the number, magnitude, and spacing of doses; (ii) use of statistical methodology that adjusts for potentially confounding factors such as survival, body weight, and litter effects; (iii) multiple comparison adjustments for the large number of variables evaluated; (iv) use of historical control data; and (v) development of appropriate statistical methodology to permit extrapolation of experimental results from high to low doses and from species to species.


  • carcinogenicity bioassays;
  • developmental toxicology;
  • risk assessment;
  • dose selection;
  • litter effects;
  • extrapolation;
  • covariates;
  • simultaneous inference