The previous chapters provide the foundation for the Bayesian approach to agreement. Chapter 6 will introduce the reader to estimating the accuracy of a test when several readers are involved in interpreting the test scores. It is important to remember that test accuracy depends not only on the medical device that gives the test scores, but also on the various other elements involved in measuring accuracy. Probably the most important factor to take into account are the various readers who have the main responsibility of reporting the accuracy of the test. Chapters 4 and 5 reported several examples that involved multiple readers.