Inter-reader reliability of MRI and CT Node Reporting and Data System 1.0 (Node-RADS) for mesorectal lymph nodes in rectal cancer.

The number of Node-RADS scored per reader was 242, corresponding to 968 values to be compared for agreement assessment. Fleiss' κ for Node-RADS score among all readers was 0.65 (substantial agreement). Analysis of the individual categories of the Node-RADS demonstrated a good agreement between all readers (κ > 0.61). A moderate positive correlation was documented between the Node-RADS and the likelihood of nodes being metastatic on histology.ConclusionThe Node-RADS score exhibited good inter-reader reliability between experienced radiologists and those still in training.