Mutation Research, 153 (1985) 135-166 135 Elsevier MTR 07186 The carcinogenicity prediction and battery selection (CPBS) method: a Bayesian approach Vira Chankong 1, Yacov Y. Haimes 1, Herbert S. Rosenkranz 2 and Julia Pet-Edwards 1 I Department of Systems Engineering, and 2 Center for the Environmental Health Sciences, Case Western Reserve University, Cleveland, OH 44106 (U.S.A.) (Received12 April 1984) (Revision received24 October 1984) (Accepted 31 October 1984) Summaff Recently, a large number of relatively inexpensive in vitro short-term tests have been developed to help predict the carcinogenicity of chemicals. The carcinogenicity prediction and battery selection (CPBS) method utilizes the results of such short-term tests to screen for chemicals that are most likely to cause cancer. The method is an integrated approach for analyzing large, often sparsely filled, data bases containing short-term test results, which often have only marginal representation of known non-carcino- gens. The CPBS method is developed for the purpose of (i) determining the reliability and predictive capability of individual and batteries of short-term tests, and (ii) developing a strategy for formulating and selecting optimally preferred batteries of short-term tests for screening chemicals for further testing. The term 'optimally preferred' connotes the best acceptable combination of tests in terms of trade-offs among the multiple attributes of each test and resulting battery (e.g., cost, sensitivity, specificity, etc.). The CPBS method consists of 5 major tasks: (1) data consolidation, (2) parameter estimation, (3) predictivity calculation, (4) battery selection and (5) risk assessment. Although there is a great need for more research and improvement, the CPBS method at its present stage should add an important method to the maze of the thousands of new chemicals that are introduced into drugs, foods, consumer goods and to the environment every year. This method should also provide an enhanced identification procedure for classifying chemicals more accurately as suspected carcinogens or non-carcinogens. I. Introduction Epidemiological and occupational exposure studies of human together with experimental re- sults on laboratory animals have shown that cer- tain synthetic and natural chemicals can produce cancer in humans (U.S. Congress, 1981). Each year, more new chemicals are introduced into drugs, foods, consumer goods and the environ- ment. Yet, for many of these chemicals, the health effects on humans are unknown. It is very im- portant that a good identification procedure be developed which will accurately classify chemicals as suspected carcinogens or non-carcinogens. With such a system in place, the regulatory agencies can take appropriate measures to prevent or reduce human exposure to the higher-risk chemicals. Such regulatory actions can result in an overall reduc- tion in the risk of cancer. At the present, in the United States, regulatory decisions are based primarily on the results of animal carcinogenicity bioassays. These tests are 0165-1110/85/$03.30 © 1985 ElsevierScience Publishers B.V. (BiomedicalDivision)