Basic Principles Of ROC Analysis

Question 1

What is ROC analysis used in clinical epidemiology?

Answer 1

to quantify how accurately medical diagnostic tests (or systems) can discriminate between two patient states, typically referred to as “diseased” and “nondiseased”

määrällisesti selvittää, kuinka tarkasti lääketieteelliset diagnostiset testit (tai järjestelmät) voivat erottaa kaksi potilastilaa, joita yleensä kutsutaan “sairaiksi” ja “ei-sairaiksi”

Question 2

What does ROC curve show?

Answer 2

The complete separation of the two underlying distributions implies a perfectly discriminating test while complete overlap implies no discrimination. The ROC curve shows the trade off between the true positive fraction (TPF) and false positive fraction (FPF) as one change the criterion for positivity.