ABSTRACT
Epidemiology is the study of health and illness in human populations. Case-control and cohort studies are the real mainstays of epidemiology and the sources of the best dose-response functions. The big benefit of epidemiology from the cancer risk assessment standpoint is that it provides the information necessary to prevent unnecessary cancers in a much wider population. Epidemiology is often disparaged on the basis that, unlike toxicology, it can only show associations and cannot demonstrate causality. Epidemiology is the primary source of several dose-response functions widely used in quantitative cancer risk assessment. An example of how an extrapolated dose-response function can give an inaccurate prediction of cancer risk and how epidemiology can resolve the discrepancy was mentioned earlier. Epidemiology is an important source of dose-response information for risk assessment. Biologic markers are a subject of considerable interest and controversy in epidemiology.
