Table 2.
Comparison of c-statistic, category-free continuous NRI, and IDI and their 95% confidence intervals in the “training set,” “test set,” and the entire cohort by base models, lipids, and their combinations to predict progression of chronic kidney disease to end-stage kidney disease
| Models | Training set (Npatient = 134) |
Test set (Npatient = 66) |
||||
|---|---|---|---|---|---|---|
| C (95% CI) | NRI | IDI (95% CI) | c (95% CI) | NRI | IDI (95% CI) | |
| Base (eGFR + UPCR) | 0.83 (0.76–0.90) | Sensitivity: 31/57 | – | 0.78 (0.67–0.89) | Sensitivity: 6/22 | – |
| Specificity: 41/77 | Specificity: 18/44 | |||||
| FDR-driven models | ||||||
| Lipids (n = 3) | 0.86 (0.79–0.92)a | Event NRI: 31/57 | 0.22 (0.15–0.29)b | 0.81 (0.70–0.93) | Event NRI: 10/22 | 0.28 (0.16–0.40)b |
| Nonevent NRI: 49/77 | Nonevent NRI: 26/44 | |||||
| Overall NRI: 1.18b | Overall NRI: 1.05b | |||||
| Lipids + base model | 0.92 (0.88–0.97)a | Event NRI: 53/57 | 0.23 (0.16–0.30)b | 0.91 (0.83–0.99)a | Event NRI: 12/22 | 0.38 (0.25–0.52)b |
| Nonevent NRI: 49/77 | Nonevent NRI: 30/44 | |||||
| Overall NRI: 1.34b | Overall NRI: 1.23b | |||||
| RF-driven models | ||||||
| Lipids (n = 4) | 0.89 (0.83–0.95)a | Event NRI: 35/57 | 0.28 (0.20–0.35)b | 0.85 (0.76–0.95)a | Event NRI: 10/22 | 0.28 (0.16–0.41)b |
| Nonevent NRI: 53/77 | Nonevent NRI: 26/44 | |||||
| Overall NRI: 1.30b | Overall NRI: 1.05b | |||||
| Lipids + base model | 0.94 (0.90–0.98)a | Event NRI: 41/57 | 0.30 (0.22–0.39)b | 0.93 (0.87–0.99)a | Event NRI: 12/22 | 0.40 (0.26–0.53)b |
| Nonevent NRI: 59/77 | Nonevent NRI: 30/44 | |||||
| Overall NRI: 1.49b | Overall NRI: 1.23b | |||||
| PLS-DA driven models | ||||||
| Lipids (n = 6) | 0.92 (0.87–0.97)a | Event NRI: 37/57 | 0.36 (0.25–0.42)b | 0.80 (0.69–0.91) | Event NRI: 8/22 | 0.20 (0.09–0.31)b |
| Nonevent NRI: 53/77 | Nonevent NRI:24/44 | |||||
| Overall NRI: 1.34b | Overall NRI: 0.91b | |||||
| Lipids + base model | 0.95 (0.92–0.99)a | Event NRI: 43/57 | 0.37 (0.28–0.45)b | 0.90 (0.82–0.97)a | Event NRI: 12/22 | 0.27 (0.15–0.39)b |
| Nonevent NRI: 65/77 | Nonevent NRI: 24/44 | |||||
| Overall NRI: 1.60b | Overall NRI: 1.09b | |||||
P values are comparisons with the corresponding base model. The components of FDR-driven model were DAG 36:0, DAG 32:0, MAG 16:0. The components of the RF-driven model were DAG 36:0, DAG 32:0, MAG 16:0, and PC 34:3. The components of the PLS-DA-driven model were DAG 36:0, DAG 32:0, MAG 26:2, MAG 20:0, MAG 16:0, and PC 34:3.
CI, confidence interval; DAG, diacylglycerol; eFGR, estimated glomerular filtration rate; FDR, false discovery rate; IDI, integrated discrimination improvement; MAG, monoacylglycerol; NRI, net reclassification improvement; PC, phosphatidylcholine; PLS-DA, partial least square-discriminant analysis; RF, Random Forest; UPCR, urine protein-to-creatinine ratio.
P < 0.05, bP < 0.001.