Incidence

Rate with which new events or cases occur during a certain period of time. Compare: Prevalence.

The number of new cases of a disorder that occurs during a specified time period.

The frequency with which a disease occurs.

The rate of new cases of a disease in a specific population.

The number of new cases of a disease during a given period of time.

In epidemiology, the number of cases of disease, infection, or some other event having their onset during a prescribed period of time in relation to the unit of population in which they occur. It measures morbidity or other events as they happen over a period of time: the number of accidents occurring in a manufacturing plant during a year in relation to the number of employees in the plant: or the number of cases of mumps occurring in a school during a month in relation to the pupils enrolled in the school. Usually refers only to the number of new cases, particularly of chronic diseases. The incidence of common colds is high relative to their prevalence. In health economics, the distribution of a tax among groups, usually income groups, in the population. Nominal incidence is the distribution mandated by law, such as a specified division of a payroll tax between employers and employees. Ultimate incidence is the distribution after the income effects of the tax are allowed for. For example, most economists feel that the employer’s share of a payroll tax is ultimately borne by the employees in lower wages or consumers in higher prices.

The number of times something happens in a specific population over a period of time.

The number of new events or cases of a disease in a population within a specified time period.

Number of times an event occurs in a given period of time, as the number of times a given disease occurs during a year.

A rate that measures the frequency with which a condition or disease occurs in a group of people during a specified period of time. To calculate incidence, the number of new cases of the disease (for example, 100 in a year) is divided by the total population (for example, an average of 10,000 through the year) to find the rate (0.01).

The number of specified new events taking place in a defined period of time in a given area or population. It usually refers to cases of disease or injury, and is the numerator in the calculation of an incidence rate for the event in question. The denominator is the population at risk (3) within the given time period. Incidence is often confused with “prevalence,” which applies to the number of events or cases of disease present in a given population at a given time.

One of the main ways to measure the frequency of a disease in a particular population. The incidence of a disease is the number of new cases that occur during a particular time, usually one year. prevalence, the other measure, is the total number of cases of disease present in a community at any one time, so it covers both old and new cases.

The frequency of new cases of a disease or condition in a specific population or group.

The number of new cases of a disease in a specified population over a defined period of time. The incidence of MS in the United States is approximately 10,000 newly diagnosed people per year.

The pace at which a disease progresses within a specific population over a period of time is known as the disease’s rate of advancement.

Incidence is one of the two main metrics (the other being prevalence) used to evaluate the commonality of a disease in a specified population. It refers to the count of new disease cases that surface within a specific time frame (e.g., 17 new cases per 100,000 individuals annually).