Case fatality ratio

Case fatality ratio (CFR), also known as case fatality rate or case fatality risk, is a epidemiological measure that quantifies the severity of a disease by indicating the proportion of reported cases of a specified disease or condition which are fatal within a specified time.

Definition[edit | edit source]

The case fatality ratio is defined as the number of deaths from a specified disease over a defined period of time divided by the number of individuals diagnosed with the disease during that time; the resulting ratio is then multiplied by 100 to yield a percentage. The CFR is a measure of disease severity and is used to compare the relative severity of different diseases.

Calculation[edit | edit source]

The CFR is calculated by dividing the number of deaths caused by a disease by the total number of cases of that disease, then multiplying the result by 100 to get a percentage. The formula is as follows:

CFR = (Number of deaths / Number of cases) * 100%

Limitations[edit | edit source]

While the CFR is a useful measure of disease severity, it has several limitations. It is highly dependent on the accuracy of reporting of both cases and deaths, and can be influenced by factors such as the availability and quality of healthcare, the age and health status of the population, and the stage of the disease at which it is diagnosed.

Use in Public Health[edit | edit source]

In public health, the CFR is used to monitor and compare the severity of diseases, and to guide strategies for disease prevention and control. It is particularly important in the context of pandemics and epidemics, where it can provide an indication of the potential impact of a disease on a population.