A community health nurse participating in planning programs for the coming year considers incidence rates to better understand the needs of the community. Which statement below is the most accurate explanation of incidence rates?

A. New cases of a disease or condition in a community over a period of time are included in incidence rates.
B. The number of all cases of a specific disease or condition in a population at a given point in time relative to the population at the same point in time is included in incidence rates.
C. Incidence rate refers to the number of new cases of a disease in those exposed to the disease.
D. The term incidence rate refers to the percentage of deaths in a specific period of time from a specific cause.

Incidence rates describe the occurrence of new cases of a disease or condition in a community during a period of time relative to the size of the population at risk for that disease or condition during that same time period. In calculating this rate, the numerator is the number of new cases during the specific period of time, and the denominator consists only of those who are at risk for developing the disease or condition during the specific period of time. A prevalence rate is the number of all cases of a specific disease or condition in a population at a given point in time relative to the population at the same point in time. Attack rates document the number of new cases of a disease in those exposed to the disease. The percentage of deaths in a specific period of time from a specific cause refers to the mortality rate.