Collaborative Behavioral Teratology Study: background and overview.

Organization of the Collaborative Behavioral Teratology Study began in 1978 because of concern about potential postnatal dysfunction following developmental chemical exposure. The study design was focused primarily on the evaluation of reliability of behavioral testing methods, the sensitivity of these methods to alterations produced by prenatal chemical exposure, and the effects of litter, sex of the animals and prior testing experience on behavioral responses. The test methods and chemicals used were selected from the literature available at that time using certain specific criteria. NCTR served as the pilot testing laboratory, and five additional laboratories participated in the study, using a standardized protocol, testing equipment and procedures. The results of the study are presented in other papers in this issue, and give ample evidence for consistency of the behavioral measures used within and between studies, and within and between laboratories. The issues of sensitivity, sex, litter and prior testing experience were addressed within the framework of this study design, but further systematic evaluation of chemicals and methods is encouraged, as exemplified by the invited papers in this issue.