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Last Edited: 6/2/2001

What is a surveillance system?

Surveillance systems are generally designed to attain complete or nearly complete coverage of every identified instance of a defined condition in a specific population (for instance, a cancer registry). Surveillance systems can be used to estimate the background incidence and prevalence of adverse effects, and trends can be analyzed across time and between populations or geographic areas. Surveillance systems can identify increases or decreases in the occurrence of deaths from specific diseases and thus suggest or test hypotheses related to environmental exposures.