Is Positive Percent Agreement the Same as Sensitivity

Written by | 16/08/2023

If you`re new to the world of statistics, you may have come across the terms “positive percent agreement” and “sensitivity” and wondered if they were the same thing.

In short, they are not the same, but they are related.

Positive percent agreement (PPA) is a measure of how often a test correctly identifies the presence of a particular condition. It is calculated by dividing the number of true positives (people who actually have the condition and test positive for it) by the sum of true positives and false negatives (people who have the condition but test negative for it).

On the other hand, sensitivity is a measure of a test`s ability to correctly identify those who have a particular condition, regardless of whether they test positive or negative. It is calculated by dividing the number of true positives by the sum of true positives and false negatives.

So while PPA and sensitivity may seem similar, they are actually measuring slightly different things. PPA is focused on the positive result (i.e., detecting the condition when it is present), while sensitivity is focused on overall accuracy in identifying the presence of the condition.

That being said, PPA and sensitivity are related, and a high PPA generally indicates a high sensitivity. However, it`s important to remember that a test`s accuracy can still be affected by factors such as the prevalence of the condition in the population being tested, the quality and reliability of the testing method, and the criteria used to define “true” positives and negatives.

In conclusion, while PPA and sensitivity are not the same thing, they are related and both important measures of a test`s accuracy in identifying the presence of a particular condition. As with any statistical analysis, it`s important to interpret the results carefully and consider all relevant factors.