Introducing new measures of inter- And intra-rater agreement to assess the reliability of medical ground truth

In this paper, we present and discuss two new measures of inter- and intra-rater agreement to assess the reliability of the raters, and hence of their labeling, in multi-rater setings, which are common in the production of ground truth for machine learning models. Our proposal is more conservative of other existing agreement measures, as it considers a more articulated notion of agreement by chance, based on an empirical estimation of the precision (or reliability) of the single raters involved. We discuss the measures in light of a realistic annotation tasks that involved 13 expert radiologists in labeling the MRNet dataset.