Statistical models for assessing agreement in method comparison studies with replicate measurements.

Method comparison studies are usually analyzed by computing limits of agreement. It is recommended that replicate measurements be taken by each method, but the resulting data are more cumbersome to analyze. We discuss the statistical model underlying the classical limits of agreement and extend it to the case with replicate measurements. As the required code to fit the models is non-trivial, we provide example computer code to fit the models, and show how to use the output to derive measures of repeatability and limits of agreement.