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SEER*Stat Tutorials: Calculating Age-adjusted Rates

An age-adjusted rate is a weighted average of the age-specific (crude) rates, where the weights are the proportions of persons in the corresponding age groups of a standard population. The potential confounding effect of age is reduced when comparing age-adjusted rates computed using the same standard population. Several sets of standard population data are included in SEER*Stat. These include the 2000 US standard population as well as standard millions for the US population (1940, 1950, 1960, 1970, 1980, 1990, and 2000), the 1991 Canadian population, the European population, and the world population (see 2000 US Standard Population vs. Standard Million for more discussion). The age-adjusted rate for an age group comprised of the ages x through y is calculated using the following formula:

formula for age-adjusted rate

View the steps to calculate an age-adjusted rate.