UCEL lion

home icon

Reusable Learning Object

Prevalence

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

 

section -- section 1 gif -- 2 -- 3 -- resources
next button
------------------------------------
Page created: 5 June, 2002
By: Dawn Leeder
Last updated: 2 March, 2012 5:13 PM
By: Alan Leeder