Rates: Age-Specific

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RATES: AGE-SPECIFIC

An age-specific rate is the rate measured in a particular age group. The numerator and the denominator for this rate refer to the same age group, that is, both have the same age distribution. Thus, for instance, the age-specific death rate of persons aged 45 to 64 is:

Age-specific rates are normally used to display aspects of health experience, such as causes of death, for the population of a nation or of jurisdictional divisions such as states, cities, and counties within a nation; they are also used to compare the health and mortality experience among many nations. Usually, these rates are separately tabulated for males and females, to display "age-sex-specific rates," and if the number of cases or events is large enough to generate stable rates, they are further subdivided to display "age-sex-cause-specific rates." For example, trends over time in the death rates from lung cancer among both males and females aged 45 to 64 demonstrate a sharp rise in the rates since the 1950sfirst among men, then among womenreflecting the trends in smoking behavior of the two sexes in the second half of the twentieth century.

John M. Last

(see also: Incidence and Prevalence; Rates; Rates: Adjusted; Rates: Age-Adjusted )