Enter the total number of new cases and the total number of people in the population at risk to determine the cumulative incidence.

Cumulative Incidence Formula

The following formula is used to calculate the cumulative incidence. 

CI = NC / TP
  • Where CI is the cumulative incidence
  • NC is the number of new cases of a disease
  • Tp is the total population at risk

To calculate cumulative incidence, divide the number of new cases by the total population at risk.

Cumulative Incidence Definition

A cumulative incidence is a ratio of the number of new cases of a disease to the total population that could be exposed to the disease.

Cumulative Incidence Example

How to calculate cumulative incidence?

  1. First, determine the number of new cases.

    Measure the total number of new cases of the disease.

  2. Next, determine the total population.

    Calculate the total population at risk.

  3. Finally, calculate the cumulative incidence.

    Calculate the cumulative incidence using the equation above.

FAQ

What is cumulative incidence?

A cumulative incidence rate is the ratio of the number of new cases of a disease to the total population at risk over a given time period.