Predictive Values Calculator

setSliderColor has been deprecated and will be removed in a future release of shinyWidgets. If you absolutely need to use this function, copy the source code into your project https://github.com/dreamRs/shinyWidgets/blob/26838f9e9ccdc90a47178b45318d110f5812d6e1/R/setSliderColor.R

Introduction

This shiny app calculates the positive and negative predictive values for a diagnostic test with particular sensitivity and specificity. Results are produced for a range of prevalences.

Background

Background on the relationship between positive/negative predictive value and prevalence can be found here or there is more general information on wikipedia .

Use the sliders below to change the value of the sensitivity and specificity to match your diagnostic test.

More options

If you are looking for a more precise, or a very small, prevalence value you select a specific range for the prevalence. The calculator will split this range into 100 steps.

Results

The plot below shows the positive and negative predictive values for a range of prevalences, based on the sensitivity and specificity shown on the sliders.

For precise values, hover over the point and a tooltip will appear.

The results are also shown in the table below. The table is sortable and searchable by prevalence.