A novel approach to determine two optimal cut-points of a continuous predictor with a U-shaped relationship to hazard ratio in survival data: simulation and application

Table 5 Performance of different estimated cut-points of FIB in Cox models by 100-times five-fold cross-validation

	Performance measures (mean ± standard error)
Method	c-index	CPE	IBS	R _PM ²	R _D ²
Median	0.552 ± 0.006	0.554 ± 0.005	0.141 ± 0.004	0.037 ± 0.009	0.065 ± 0.017
Q1Q3	0.555 ± 0.010	0.557 ± 0.009	0.141 ± 0.005	0.040 ± 0.012	0.036 ± 0.015
minP	0.538 ± 0.009	0.543 ± 0.008	0.142 ± 0.004	0.027 ± 0.010	0.047 ± 0.019
OEHR	0.569 ± 0.010	0.572 ± 0.009	0.138 ± 0.006	0.069 ± 0.015	0.076 ± 0.020

Median denotes using the median value of the continuous covariate as a cut-point. Q1Q3 denotes using the upper and lower quartiles values as cut-points. MinP denotes the single cut-point minimum p-value method with the log-rank test. OEHR denotes the optimal equal-HR method proposed in this study

ISSN: 1471-2288