The occurence of deaths in a given population.

Crude mortality rate :
The number of deaths in a specified period (usually one year) divided by the average total population in that period (usually taken as the mid-year population). The rate is normally expressed per 1,000 population.

Standardized mortality rate
Adjusted mortality rate for a given cause of death or country calculated by applying a fixed age structure to the age-specific rates observed each year. This technique eliminates the effects of population age structure so that mortality can be compared over time and space.

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