Etiologic Predictive Value (EPV) is designed to calculate the predictive value of test while considering the possibility of carriers of the marker the test is designed to detect. EPV produces predictive value of tests without requiring a gold standard . It has been used to establish if a potential pathogen is a pathogen or merely a passenger when found in patients having symptoms of an infectious disease . However, it can be used in other circumstances as well. More background information can be found on the web page introducing EPV. You can download an Excel file that calculates EPV:

The online calculator below calculates Positive and negative EPV with 95% confidence intervals. The confidence intervals for positive and negative EPV will simultaneously be 95% (adsjustment for calculating two confidence intervals is done automatically). Version 3.0 was launced on 13th of August 2024. Updates from previous version 2:

1. Allows calculation of positive EPV even if the proportion of positive tests are higher among healthy subjects compared to symptomatic patients.
2. Allows calculation even if there are no positive tests among cases or controls (substitutes 0 with 1 to enable calculation of approximate EPV).
3. Fixed a few minor glitches that only were relevant in very unusual scenarios.
4. Simplification and clarification of instructions

(Version 2 is not available. The old version 1 is found here: https://www.infovoice.se/fou/epv/calc/index.htm but we recommend using the latest version found below)

References