AKI Class Switching
AKI
We defined class switching as neonates who moved from 1 stage of AKI to another after correcting for fluid balance. For example, a neonate with a positive fluid balance with no AKI by uncorrected serum creatinine may have had stage 2 AKI after correcting serum creatinine for fluid balance (ie, unveiled AKI). Conversely, a neonate with substantial diuresis and stage 1 AKI based on uncorrected serum creatinine may have been recategorized to no AKI after correction for a negative fluid balance (ie, overdiagnosed AKI) (eTable 1 in 