Question

Which is best in order to make a comparison between two populations?

• A. Standardised mortality rate
• B. Disease specific death rate
• C. Proportional mortality rate
• D. Age specific death rate

Hint:

Age-adjusted (standardised) rates remove structural differences between populations.

Answer 1

The Correct Option is A

Step 1: Understanding the Question:
The question asks which measure is best suited to compare death rates between two populations that may differ in structure, such as age distribution.

Step 2: Key Concept:
Crude death rates cannot be compared directly between two populations if their age structures differ, because a population with more old people will always show a higher crude death rate even if health care is the same. Standardisation (direct or indirect) adjusts for this difference and gives a fair, comparable figure.

Step 3: Detailed Explanation:
The standardised mortality rate (also called the adjusted death rate) recalculates the death rate as if both populations had the same standard age structure. This removes the effect of age composition and lets the true difference in mortality risk be seen.
Disease specific death rate only measures deaths from one disease, not the general mortality experience, so it does not correct for population structure.
Proportional mortality rate shows what fraction of total deaths is due to a cause, but it depends heavily on the total number of deaths and is not adjusted for population structure either.
Age specific death rate is useful within one age band but does not by itself give a single summary figure to compare two whole populations.

Step 4: Final Answer:
The standardised mortality rate is the correct tool for comparing two populations because it removes the confounding effect of age structure.
\[ \boxed{\text{Standardised Mortality Rate}} \]