2. Performance of two radiomics signatures and combined model.

Performance	Measure	Primary cohort				Validation cohort
		Handcrafted signature	Deep signature	Combined model		Handcrafted signature	Deep signature	Combined model
95% CI, 95% confidence interval; H-L test, Hosmer-Lemeshow test; sNB, standardized net benefit.
Overall	Brier score	0.191	0.182	0.159		0.220	0.231	0.211
Discrimination	C-index (95% CI)	0.739 (0.661−0.818)	0.760 (0.690−0.831)	0.829 (0.767−0.890)		0.695 (0.609−0.781)	0.777 (0.696−0.857)	0.809 (0.740−0.879)
Calibration	H-L test (P)	0.674	0.294	0.887		0.416	0.161	0.528
Clinical usefulness (T50%)	sNB	0.100	0.150	0.333		0.070	0.263	0.360