Prevalence Health Dictionary

The total number of cases of a disease at any one time in a defined population. Prevalence is often expressed as the number of cases per 100,000 people.

An epidemiological term describing the proportion of a de?ned group in the population having a condition at one point in time. It is an appropriate measure only in relatively stable conditions – for example, chronic bronchitis – and is not suitable for measuring acute illnesses.

The number of events, such as instances of a given disease, condition or other attribute, present at a particular time. Sometimes used to mean prevalence rate. When used without qualification, the term usually refers to the situation at a specified point in time (point prevalence). annual prevalence: The total number of persons with a given disease or attribute at any time during a year. lifetime prevalence: The total number of persons known to have had a given disease or attribute for at least part of their lives. period prevalence: The total number of persons known to have had a given disease or attribute at any time during a specified period. point prevalence: The total number of persons with a given disease or attribute at a specified point in time. See also “incidence”.

The number of cases of a disease or other condition existing for a given area or at a given time, for a given population. Prevalence includes both new (incidence) and existing instances of a disease.

n. a measure of morbidity based on current levels of disease in a population, estimated either at a particular time (point prevalence) or over a stated period (period prevalence). It can be expressed either in terms of affected people (persons) or episodes of sickness per 1000 individuals at risk. Compare incidence rate.