|
Crucial to rate
calculation is the determination of an appropriate denominator. For many
mortality rates, such as the crude death rate and age- and cause-specific
death rates, and also some incidence rates, denominators typically derive
from the census. However, population census data perform another very useful
function in descriptive epidemiology. They furnish the building blocks for
constructing population pyramids. Valuable for comparisons, population
pyramids graphically display the composition of a population broken down by
age and sex. Although a pyramid is a cross-sectional snapshot of a
population, it also reflects that population’s history. |