by Thomas Zembowicz 

How to assess probability that a tumor is melanoma given positive or negative result of an ancillary test. A companion to Dermpedia Lecture: Conditional Probability For Dermatopathologists. 

Calculator:




import {Runtime, Inspector} from "https://cdn.jsdelivr.net/npm/@observablehq/runtime@4/dist/runtime.js"; import define from "https://api.observablehq.com/@tzembo/bayes-theorem.js?v=3"; (new Runtime).module(define, name => { if (name === "defs") return Inspector.into("#observablehq-a606f69e .observablehq-defs")(); if (name === "viewof sensitivity") return Inspector.into("#observablehq-a606f69e .observablehq-viewof-sensitivity")(); if (name === "viewof specificity") return Inspector.into("#observablehq-a606f69e .observablehq-viewof-specificity")(); if (name === "viewof prevalence") return Inspector.into("#observablehq-a606f69e .observablehq-viewof-prevalence")(); if (name === "eq1") return Inspector.into("#observablehq-a606f69e .observablehq-eq1")(); if (name === "eq2") return Inspector.into("#observablehq-a606f69e .observablehq-eq2")(); if (name === "viewof population") return Inspector.into("#observablehq-a606f69e .observablehq-viewof-population")(); if (name === "table") return Inspector.into("#observablehq-a606f69e .observablehq-table")(); });

Sources:

Toph Tucker, Sensitivity and Specificity (sketch)

Wayne W. LaMorte, MD, PhD, MPH (Boston Universtiy School of Public Health), "The Role of Probability: Bayes Theorem"