Period prevalence

In epidemiology, Period prevalence is the proportion of the population with a given disease or condition over a specific period of time. It could describe how many people in a population had a cold over the cold season in 2006, for example.

It is expressed as a percentage of the population and can be described by the following formula:

Period prevalence = Number of cases that occurred in a given period ÷ Number of people in the population during this period