Encyclopedia > Prevalence

  Article Content


The prevalence of a disease is defined as follows:

Prevalence =

Number of cases of a disease present
in a population at a specified time
Number of individuals in the population
at that specified time

Prevalence is useful because it is a measure of the commonality of disease. It helps physicians with the probability of certain diagnoses and is routinely used by epidemiologists, health care providers, government agencies, and insurance companies.

Prevalence is not to be confused with incidence, which provides a measure of occurrences of a disease in a specified time interval. Prevalence involves all affected individuals, regardless of the date of contraction.

To illustrate, a disease with a long duration that was spread widely in a community in 2002 will have a high prevalence in 2003 (assuming it has a long duration) but it might have a low incidence rate in 2003. Conversely, a disease that is easily transmitted but has a short duration may have a low prevalence and a high incidence.

All Wikipedia text is available under the terms of the GNU Free Documentation License

  Search Encyclopedia

Search over one million articles, find something about almost anything!
  Featured Article

... winters. Economy Main article: Economy of Latvia Latvia's transitional economy recovered from the 1998 Russian financial crisis, largely due to the previous ...