The Zombie Plot: A Simple Graphic Method for Visualizing the Efficacy of a Diagnostic Test

AJR Am J Roentgenol. 2016 Oct;207(4):W43-W52. doi: 10.2214/AJR.15.15869. Epub 2016 Aug 9.

Abstract

Objective: One of the most important jobs of a radiologist is to pick the most appropriate imaging test for a particular clinical situation. Making a proper selection sometimes requires statistical analysis. The objective of this article is to introduce a simple graphic technique, an ROC plot that has been divided into zones of mostly bad imaging efficacy (ZOMBIE, hereafter referred to as the "zombie plot"), that transforms information about imaging efficacy from the numeric domain into the visual domain.

Conclusion: The numeric rationale for the use of zombie plots is given, as are several examples of the clinical use of these plots. Two online calculators are described that simplify the process of producing a zombie plot.

Keywords: ROC; imaging efficacy; likelihood ratio; sensitivity; specificity.