"The major disadvantage of crude rates is that:

A. They may not allow for comparison of populations that differ
B. They do not permit comparisons of populations that vary in age distribution.
C. They are difficult to calculate from available data sources.
D. All of the above."

The option D) All of the above is correctThe major disadvantage of crude rates is that:They may not allow for comparison of populations that differ They do not permit comparisons of populations that vary in age distribution. They are difficult to calculate from available data sources.

Hence options A ,B and C are correct

Step-by-step explanation:

Given that crude rate

To find the disadvantage of crude rate :

A crude rate is the number of new cases (or deaths) occurring in a specified , it can be expressed as the number of cases per 100,000 population at risk.

The major disadvantage of crude rates is that:They may not allow for comparison of populations that differ They do not permit comparisons of populations that vary in age distribution. They are difficult to calculate from available data sources.

Hence options A ,B and C are correct

∴ The option D) All of the above is correct.