Statistical issues in carcinogenic risk assessment.

Considerable progress has been made on the development of a variety of analytical methods to aid in the carcinogenic risk associated with exposure to both occupational and environmental agents. Although the development of these methods has been accompanied by consideration of many statistical issues, there are many areas where additional effort could be directed if these analytical methods are to provide the most appropriate interpretation of risk. These issues include methods of combining multiple studies to obtain an overall risk estimate, the robustness of the statistical model, methods of selection among competing models, an assessment of the effect of different measures of exposure on the estimated dose-response relationship, and development of surveillance methodology. These issues are discussed, and productive areas of future research are indicated.