External validation of the updated international IgA nephropathy prediction tool in a Chinese population

In this external validation, the updated post-biopsy IIgAN-PT demonstrated improved calibration over the original IIgAN-PT for risk assessment at 1-year post-biopsy, leading to more accurate absolute risk estimates. However, due to the limitations of the updated IIgAN-PT in distinguishing between low-risk and intermediate-risk patient groups, its application value for refined risk stratification in clinical decision-making is constrained. Registry: Chinese Clinical Trial Registry, TRN: ChiCTR2400093550, Registration date: 06 December 2024.