Prevalence
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The easiest way to describe diseases in populations is to just count the number of cases.
But this information is more useful if it's given in the context of a whole defined population.
Then you can see the proportion of people who have the disease at any one time.
This is called "prevalence" and can be expressed symbolically: a/a+b.
This is a proportion. A ratio would not include 'a' in the denominator: a/b
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Page created: 5 June, 2002
By: Dawn Leeder
Last updated: 26 September, 2019 12:38 PM
By: Alan Leeder