American Health Services Corporation has developed a series of software programs which is marketed under the trademark SENTRY_ Health Surveillance. This software is part of an integrated system designed to assist medical personnel in the management of medical information in occupational and nonoccupational settings. Its surveillance features include the ability of comparing population groups to detect statistically significant differences in the incidence of adverse health effects. The natural extension of this system would include the ability to perform risk comparisons with greater accuracy than those methods based on traditional statistics.The specific goal of this project is to apply recently developed algorithms for nonparametric density estimation to the problem of risk assessment in a health analysis setting. The tasks include adapting various density estimation algorithms to health data sets, considering the problems of parameter selection and numerical complexity for these algorithms, developing risk analysis methods which use both formal probability models and the nonparametric density estimates, testing these methods on various data sets, and developing prototype software that allows us to predict the commercial viability of adding these methods to the SENTRY system.National Center for Research Resources (NCRR)