Sample Size for Measuring Rates
Another kind of variable of interest is a rate. Measuring rates may not be feasible or very meaningful at a local level, but they certainly mean a lot at a higher level (larger geographic area/population.
Some examples of rates that are oftne studied and followed by development agencies are:
1. Infant Mortality Rate (IMR)
2. Maternal Mortality Rate (MMR)
3. Many low prevalence variables/indicators where proportion may not be applicable, but instead a per thousand, per hundred thousand or per million is more appropriate
For measuring such rates, refer to the formulae below:
Some examples of rates that are oftne studied and followed by development agencies are:
1. Infant Mortality Rate (IMR)
2. Maternal Mortality Rate (MMR)
3. Many low prevalence variables/indicators where proportion may not be applicable, but instead a per thousand, per hundred thousand or per million is more appropriate
For measuring such rates, refer to the formulae below:
Single Rate - Absolute Precision Method
Single Rate - Power Method
It is one thing to measure a single rate, and it is another thing to compare two rates. It is not really a right or recommended way to use the sample size calculation for single rate and apply it to two groups separately and then compare the results. Hence, for comparing two rates, refer to the formulae below:
Compare Two Rates - Power Method
Compare Two Rates - Precision Method
Compare Two Rates - Power Calculation
Compare Two Rates - Detectable Difference
