Interobserver Agreement in Hepatitis C Grading and Staging and in the Banff Grading Schema for Acute Cellular Rejection: The “Hepatitis C 3” Multi-Institutional Trial Experience

Abstract Context.—Establishing adequate interobserver agreement is crucial not only for standardization of patient care but also to ensure validity of findings in multi-institutional trials. Objective.—To evaluate interobserver agreement in assessing chronic hepatitis C (HCV) and acute cellular rejection (ACR) among 17 hepatopathologists involved in the “Hepatitis C 3” trial. Design.—The trial is a randomized multicenter (17 institutions) study involving 312 patients undergoing transplantation for HCV. Patients are randomized to 3 treatment arms. For final data analysis, all biopsy specimens are reviewed by a central pathologist (G.J.N.). Recurrence of HCV is evaluated according to the Batts and Ludwig schema. The 1997 Banff schema is used to evaluate ACR. To assess interobserver agreement, hematoxylin-eosin–stained sections from 11 liver biopsy specimens (6 HCV and 5 ACR) were sent by the central pathologist to 16 local pathologists from 13 institutions. Statistical analysis was performed on raw ACR/HCV ...