Diagnostic test evaluation and comparison
Numbers of false positives to a test
This utility calculates the expected probability of numbers of false positive results
to a test for a given sample size and test specificity, assuming the sample is from an uninfected population. It answers the question:
For a given sample size and test specificity, and assuming that all animals are uninfected, what is the probability that there will be 1, 2, 3 etc false positives? .
It also answers the related questions:
What is the probability of x (1, 2, 3, etc) or more false positive results? and
What is the probability of x (1, 2, 3, etc) or less false positive results?.
Inputs:
- Test unit specificity; and
- Sample size.
Outputs:
A table and plot of probabilities for each of the following:
- the likely numbers of false positives (x);
- less than or equal to x false positives; and;
- greater than or equal to x false positives.