Table 7 Multivariate results by Cox regression (N = 1264)

Fitting model by stand linear regression

0.83 (0.78, 0.88) < 0.0001

0.89 (0.84, 0.94) < 0.0001

0.88 (0.83, 0.92) < 0.0001

Fitting model by two-piecewise linear regression

Inflection point

5940

5840

5840

  < Inflection point

0.72 (0.66, 0.79) < 0.0001

0.76 (0.70, 0.83) < 0.0001

0.74 (0.68, 0.81) < 0.0001

  > Inflection point

1.01 (0.91, 1.11) 0.9157

1.07 (0.98, 1.17) 0.1302

1.06 (0.97, 1.16) 0.2104

 P for log-likelihood ratio test

 < 0.001

 < 0.001

 < 0.001