Use of Severity Grades to Characterize Histopathologic Changes. - Schafer, Kenneth A.; Eighmy, John; Fikes, James D.; Halpern, Wendy G.; Hukkanen, Renee R.; Long, Gerald G.; Meseck, Emily K.; Patrick, Daniel J.; Thibodeau, Michael S.; Wood, Charles E.; Francke, Sabine (Toxicologic Pathology, 2018)