Studies of Diagnostic Tests | Understanding Medical Research

Accuracy is a terrible way to judge a diagnostic test. This video covers the two by two contingency table, sensitivity and specificity, positive and negative predictive value, and why a test result only means something in the context of disease prevalence. Chapters: 00:00 Introduction and goals 00:44 A 95 percent accurate test 02:17 The two by two table 03:33 Accuracy, defined and debunked 04:37 Positive and negative predictive value 06:22 Sensitivity and specificity 08:45 HIV testing in a high-prevalence group 10:49 The same test in a low-prevalence group 13:05 Take-home points Learning objectives: After watching, you'll be able to: - Explain why accuracy alone says little about a diagnostic test - Define sensitivity, specificity, positive predictive value, and negative predictive value using a two by two table - Interpret a positive test result in light of disease prevalence in the tested population 📺 Watch the full playlist on YouTube: https://www.youtube.com/playlist?list=PLh9mgdi4rNewVyTec_MVGxIbNSEeMhEsZ 🎓 Enroll on Coursera for assessments and a certificate: https://www.coursera.org/learn/medical-research 🌐 Explore more learning opportunities on Yale Online: https://online.yale.edu/courses/understanding-medical-research-your-facebook-friend-wrong