fncEBMPostTest: Computes post test probability to have a dissease based on...

In RcmdrPlugin.EBM: Rcmdr Evidence Based Medicine Plug-in Package

Description

This dialog box permits you to define the probability of a patient to have a disease before performing a diagnostic test (pre-test probability), and the likelihood ratio of the diagnostic test. Based on these two, the post-test probability to actually have the disease is computed.

This is computed the following way:
pre-test odds <- pre-test probability / (1 - pre-test probability)
post-test odds <- pre-test odds * likelihood ratio
post-test probability<- post-test odds / (post-test odds + 1)

Usage

fncEBMPostTest(.pretest, .LR)

Arguments

.pretest	Pre-test probability.
.LR	Likekihood ratio of the diagnostic test.

Value

The post-test probability of having the dissease.

Author(s)

Daniel-Corneliu Leucuta <[e-mail]>

Examples

fncEBMPostTest(.12, 5.7)

Example output

Loading required package: Rcmdr
Loading required package: splines
Loading required package: RcmdrMisc
Loading required package: car
Loading required package: carData
Loading required package: sandwich
Loading required package: effects
lattice theme set by effectsTheme()
See ?effectsTheme for details.
The Commander GUI is launched only in interactive sessions

Attaching package: 'Rcmdr'

The following object is masked from 'package:car':

    Confint

Loading required package: epiR
Loading required package: survival
Package epiR 0.9-99 is loaded
Type help(epi.about) for summary information


Loading required package: abind
Warning message:
no DISPLAY variable so Tk is not available 

# Post-test probability:[1] 0.4373402

RcmdrPlugin.EBM documentation built on May 2, 2019, 4:20 a.m.