The best evidence of an adverse human health effect is a properly conducted epidemiological study. But human beings should not be the sole test animal. Properly conducted animal studies have been shown to be preductive for carcinogenicity and toxicologic responses in human populations. We need to develop more efficient predictive animal tests for all the common serious toxic effects caused by c...

Statistical methods for the use of historical control data in testing for a trend in proportions in carcinogenicity rodent bioassays are reviewed. Asymptotic properties of the Hoel-Yanagawa exact conditional tests are developed and compared with the Tarone test. It is indicated that the Hoel-Yanagawa test is more powerful than the Tarone test. These tests depend on the beta-binomial parameters ...