Incidence (epidemiology)

[edit] Americola's celebrity biographies are provided by AmericolaWiki, a celebrity wiki. You can help contribute to Americola and edit this article.

Incidence is the number of new cases of a disease during a given time interval, usually one year.

Incidence rate, a related concept, is the incidence divided by the number of people at risk, often expressed as the incidence per 1,000.

The word "incidence" is sometimes used alone as a shorthand for "incidence rate". Although this is sloppy usage, it is frequently encountered.

Incidence can also be called the "absolute risk", indicence rate the "relative risk".

Definitions:

INCIDENCE is the number of new cases of a specific illness diagnosed or reported during a stated period of time, usually one year.

INCIDENCE RATE is the incidence divided by the number of people at risk for the disease.

Example: In a community of 5,000 people, five children per year develop measles. The incidence rate of measles in that community is 5/5000 or 1 case per 1,000 people per year.

Incidence should not be confused with prevalence, which is a measure of the total number of cases of disease in a population, rather than the rate of occurrence of new cases. Thus, incidence conveys information about the risk of contracting the disease, whereas prevalence tells us how widespread the disease is.

Example: Consider a disease that takes a long time to cure, and that was spread widely in 2002, but whose spread was arrested in 2003. This disease will have a high prevalence and a high incidence in 2002; but in 2003 it will have a low incidence, although it will continue to have a high prevalence because it takes a long time to cure.

In contrast, a disease that has a short duration may have a low prevalence and a high incidence.

See also

• Prevalence
• attributable risk
• Glossary of epidemiological termsde:Inzidenz (Medizin)

es:Incidencia fr:Incidence (épidémiologie) it:Incidenza lt:Sergamumas nl:Incidentie no:Insidens pl:Zapadalność ru:Заболеваемость sv:Incidens

Wikipedia information about Incidence (epidemiology) This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Incidence (epidemiology)". It may not have been reviewed by professional editors (see full disclaimer). Help contribute to Americola and edit this article.