Preoperative prediction of perineural invasion of rectal cancer based on a magnetic resonance imaging radiomics model: A dual-center study

Table 6 Performance of the clinical model, T2-weighted imaging + contrast-enhanced T1WI fusion sequence radiomics model, and clinical-radiomics model in the training group, as evaluated using the Delong test, integrated discrimination improvement index, and Net reclassification improvement index

Models	AUC (95%CI)	Delong test P value	IDI (95%CI)	IDI index P value	NRI (95%CI)	NRI index P value
CR model	0.889 (0.824-0.954)
Clinical	0.804 (0.727-0.881)	0.009	0.210 (0.130-0.290)	0.000	0.588 (0.271-0.904)	0.000
T2WI + T1CE	0.839 (0.757-0.921)	0.019	0.075 (0.026-0.124)	0.002	0.447 (0.164-0.731)	0.002

AUC: Area under receiver operating characteristic curve; IDI: Integrated discrimination improvement; NRI: Net reclassification improvement; CR: Clinical-radiomics; T2WI: T2-weighted imaging; T1CE: Contrast-enhanced T1WI.