Table 4.

Selection of the optimal model for identifying diabetic retinopathy (DR).

Contrast	Difference in AUC (95% CI)	P-value	IDI (95% CI)	P-value	NRI (95% CI)	P-value
Training set
Model1–Model7	0	–	<−0.01 (<−0.01, <0.01)	0.170	−0.04 (−0.44, 0.35)	0.840
Model2–Model7	−0.05 (−0.10, <0.01)	0.053	−0.10 (−0.15, −0.04)	<0.001	−0.69 (−1.06, −0.32)	<0.001
Model3–Model7	−0.06 (−0.12, −0.01)	0.021	−0.11 (−0.16, −0.05)	<0.001	−0.61 (−0.99, −0.24)	0.002
Model4–Model7	−0.06 (−0.12, 0.01)	0.096	−0.09 (−0.16, −0.02)	0.011	−0.41 (−0.80, −0.02)	0.043
Model5–Model7	−0.07 (−0.13, −0.01)	0.027	−0.12 (−0.18, −0.05)	<0.001	−0.57 (−0.95, −0.19)	0.005
Model6–Model7	−0.01 (−0.05, 0.02)	0.447	−0.03 (−0.07, 0.02)	0.228	−0.29 (−0.68, 0.11)	0.157
Testing set
Model1–Model6	0	–	<−0.01 (<−0.01, <−0.01)	<0.001	−1.10 (−1.61, 0.59)	<0.001
Model2–Model6	−0.04 (−0.16, 0.09)	0.560	−0.09 (−0.21, 0.03)	0.134	−0.50 (−1.09, 0.09)	0.114
Model3–Model6	−0.08 (−0.18, 0.03)	0.161	−0.11 (−0.22, <0.01)	0.057	−0.80 (−1.36, −0.24)	0.011
Model4–Model6	0.03 (−0.08, 0.13)	0.606	0.06 (−0.08, 0.20)	0.394	0.60 (<0.01, 1.19)	0.058
Model5–Model6	−0.07 (−0.22, 0.08)	0.367	−0.14 (−0.29, 0.01)	0.074	−0.40 (−1.00, 0.20)	0.206
Model6–Model7	0.03 (−0.03, 0.09)	0.304	0.04 (<0.01, 0.16)	0.033	1.00 (0.48, 1.52)	0.002

Model 1: LA/total n-3 PUFAs + systolic BP + duration of diabetes; Model 2: GLA/total n-3 PUFAs + systolic BP + duration of diabetes; Model 3: EDA/total n-3 PUFAs + systolic BP + duration of diabetes; Model 4: DGLA/total n-3 PUFAs + systolic BP + duration of diabetes; Model 5: AA/total n-3 PUFAs + systolic BP + duration of diabetes; Model 6: the 1st PC + the 2nd PC + systolic BP + duration of diabetes; Model 7: Total n-6/n-3 PUFAs + systolic BP + duration of diabetes.

AUC, the area under the receiver-operating-characteristic (ROC) curve; IDI, the integrated discrimination improvement; NRI, the net reclassification improvement.