Age-Adjustment in National Biosurveillance Systems
The practice of biosurveillance primarily involves measuring disease cases accurately and precisely in a given population. However, measuring the size and composition of the actual population at risk for the diseases under surveillance is just as important, particularly when the objective of surveillance is to measure rates of disease. The purpose of this chapter is to explore the issues pertaining to selection of the population denominator in population surveillance, with a particular focus on age and age-adjustment. This chapter presents an overview of several data sources commonly available to surveillance and epidemiological professionals, along with a synopsis of graphical and statistical tools to help assess and adjust for age effects in disease patterns.
KeywordsPopulation dynamics Surveillance Age-adjustment Age-period-cohort analysis Standardization
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