Answer:
Incidence and prevalence are terms commonly used in epidemiology to describe the occurrence and distribution of diseases or health conditions in a population.
Incidence: Incidence refers to the number of new cases of a specific disease or health condition that develop within a defined population over a specified period of time. It represents the rate of occurrence of new cases and provides insights into the risk of acquiring the disease.
Prevalence: Prevalence, on the other hand, refers to the total number of existing cases of a disease or health condition within a population at a given point in time. It represents the proportion of individuals in a population who have the disease and provides information about the overall burden of the condition.
Types of incidences:
Cumulative incidence: Cumulative incidence measures the risk of developing a disease over a specified period. It calculates the proportion of individuals who become affected by the disease within a specific time frame.
Incidence rate: The incidence rate, also known as the person-time incidence rate, takes into account the amount of time individuals are at risk of developing the disease. It is calculated by dividing the number of new cases by the total person-time at risk in the population.
It's worth noting that incidences can be further categorized based on the specific disease or condition being studied.
I hope this helps you!