More than 50 million animals are used in biomedical research in the world each year. It is highly desirable that this number is reduced both for ethical and for economic reasons. Better experimental ...design could lead to the use of fewer animals and improve the repeatability of animal experiments so that alternative methods would be easier to validate. Screening experiments aimed at identifying rodent carcinogens would be more powerful if more than one strain of mice and/or rats were used. Attempts to validate alternative test methods by using chemicals already tested in the Draize test for eye irritation are complicated by limited information on the interexperiment variability of the whole animal test. In academic toxicological research, surveys suggest that many experiments are poorly designed, and some seem to be unnecessarily large.
