**Core Concept**
Proportional mortality rate (PMR) is a measure used to assess the proportion of deaths due to a specific cause within a population. It is an essential tool in epidemiology, helping researchers understand the burden of different diseases and identify areas for intervention.

**Why the Correct Answer is Right**
PMR is calculated by dividing the number of deaths due to a specific cause by the total number of deaths in a population, multiplied by 100. This provides a percentage representation of the proportion of deaths attributed to that cause. For instance, if 30% of total deaths are due to cardiovascular disease, the PMR for cardiovascular disease would be 30. PMR is often used to compare the relative importance of different causes of death across different populations or over time.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not accurately describe the proportional mortality rate. PMR is a specific measure that requires the calculation of the proportion of deaths due to a cause out of the total number of deaths.
**Option B:** This option is incorrect because it is not a recognized measure in epidemiology. While it may sound similar to PMR, it is not a valid or commonly used term.
**Option C:** This option is incorrect because it does not accurately describe the proportional mortality rate. PMR is a measure of the proportion of deaths due to a specific cause, not a measure of the rate of disease occurrence.

**Clinical Pearl / High-Yield Fact**
When interpreting PMR, it's essential to consider the underlying population demographics and the specific causes of death. PMR can be influenced by factors such as age, sex, and socioeconomic status, which can vary across different populations.

**Correct Answer:** B.