Sensitivity, specificity, and how prevalence influences the reliability of test results

The effectiveness of a test is often reported in terms of the probability that it will detect positive cases. However, due to the way tests work, this is often not enough to evaluate the test's predictive value. This video describes how the prevalence of a condition in a population influences the reliability of test results.

0:00 Introduction
1:11 Sensitivity
1:42 Specificity
2:16 Error matrix
3:13 Introduction to the predictive value
4:32 Importance of disease prevalence
5:39 Implications of false positives and false negatives
6:55 How low prevalence impacts positive predictive value
8:34 Usefulness of retesting
9:10 Additional information improves predictive value

link to the retesting calculator: https://scienceprimer.com/test-sensit...
BMJ Covid-19 test calculator: https://scienceprimer.com/test-sensit...

This video is the product of a collaboration between SciencePrimer and Dr. Kerri Warren, Professor of Biology and Public Health at Roger Williams University.

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