Comment: A General Approach for Evaluating Stepwise Testing Strategies

Andrew P. Worth and Julia H. Fentem

A stepwise (hierarchical) testing strategy is an approach to hazard evaluation based on the sequential application of one or more alternative methods prior to the use of any animal tests which are considered necessary. The purpose of a stepwise testing strategy is to reduce and refine the use of animals in toxicity testing without compromising human safety. An example of such a strategy is the proposed OECD testing and evaluation strategy for eye irritation/corrosion (1), which is based on a proposal made at the OECD Workshop on Harmonization of Validation and Acceptance Criteria for Alternative Toxicological Test Methods, held in Solna, Sweden, in January 1996.