Question

In: Statistics and Probability

How to calculate 95% CI with sensitivity and specificity That is sensitivity, specificity, prevalence has been...

How to calculate 95% CI with sensitivity and specificity

That is sensitivity, specificity, prevalence has been given and 95%CI needs to be calculated, but how???

Solutions

Expert Solution

There are many ways to do it but here we are only considering the SImple Asymptotic formula.

Let p be the population sensitivity, and let r represent the number of true positives with n total positives.

The simple asymptotic formula is based on the normal approximation to the binomial distribution. The approximation is close only for very large sample sizes. The 100(1-α)% confidence limits are given by

One-sided limits may be obtained by replacing α/2 by α.

Here, Standard error is,

SImilarly we can find a CI for specificity.


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