Development of a semi-quantitative evaluation system for surveillance of bovine spongiform encephalopathy, using the analytic hierarchy process.

Evaluating surveillance results is important in estimating the risk of bovine spongiform encephalopathy (BSE) cases in a particular country, or in countries from which products are imported. Although various methods have been proposed for quantitative evaluation of surveillance results, no methods focusing on surveillance from a qualitative perspective have yet been established. The authors have developed an objective method for evaluating the qualitative aspects of BSE surveillance, based on the analytic hierarchy process. Factors related to surveillance credibility were selected through expert meetings and arranged in a hierarchical structure. These evaluation factors were also weighted, so that a points system could be used for evaluation. As a result, 13 evaluation factors comprising three-layer hierarchies were generated. When surveillance in Japan before and after a BSE case was evaluated using this evaluation system, an improvement in the quality of the surveillance was observed after the outbreak. Although this study suggests that the selection of the experts had a significant effect on the outcome, the authors believe that this method will also be applicable for establishing qualitative evaluation systems for other diseases.