Incidence

The rate of new cases of a disease in a population over time

Definition

Incidence is the number of new cases of a disease or condition that occur in a specified population during a defined time period. It measures risk and is expressed as cases per population per time (e.g., per 100,000 per year).

Incidence vs Prevalence

Incidence: New cases over time (rate).
Prevalence: Total existing cases at a point in time (proportion).

Clinical Use

Public health uses incidence to track outbreaks, evaluate prevention programs, and plan resources. Nurses may apply incidence data when designing community health initiatives.

NCLEX Relevance

Tested in community and public health nursing.