Table 5.

The comparison of Harrell’ C statistics of the adjusted Cox proportional hazard model and continuous net reclassification improvement (NRI) of baseline and enhanced model for predicting risk of death.

Models	Harrell’C statistics		Continuous NRI
	C-statistic	P value†	Overall (%) with 95% CI
Base model: age, sex, race, comorbidities*	0.63	reference
Base model + low muscle mass, weakness, and slowness as dichotomous variables
low muscle mass by height2	0.65	0.17	4.7 (−22.9, 29.2)
low muscle mass by BW	0.63	0.56	−6.0 (−33.5, 27.2)
low muscle mass by BSA	0.64	0.30	13.8 (−34.6, 35.0)
low muscle mass by BMI	0.63	0.49	15.4 (−28.5, 42.4)
weakness	0.66	0.56	33.7 (9.8, 62.7)
slowness	0.68	0.004	50.5 (24.3, 73.0)
Base model + sarcopenia, defined as low muscle mass combined with weakness
low muscle mass by height2 and weakness	0.65	0.31	−8.4 (−28.5, 20)
low muscle mass by BW and weakness	0.64	0.28	2.8 (−32.1, 27.5)
low muscle mass by BSA and weakness	0.65	0.41	14.3 (−25.5, 37.6)
low muscle mass by BMI and weakness	0.64	0.18	1.7 (−26.7, 31.5)
Base model + sarcopenia, defined as low muscle mass combined with slowness
low muscle mass by height2 and slowness	0.65	0.28	−7.1 (−28.1, 19.7)
low muscle mass by BW and slowness	0.64	0.23	0.2 (−28.1, 32.0)
low muscle mass by BSA and slowness	0.64	0.33	5.2 (−25.5, 31.1)
low muscle mass by BMI and slowness	0.64	0.74	11.8 (−10.5, 39.0)
Base model + total muscle mass, handgrip strength, and gait speed as continuous variables
muscle mass/height2	0.64	0.28	9.9 (−25.9, 34.2)
muscle mass/BW	0.63	0.15	−28.5 (−32.7, 35.7)
muscle mass/BSA	0.64	0.70	10.3 (−24.1, 38.6)
muscle mass/BMI	0.65	0.17	−5.7 (−31.3, 31.6)
handgrip strength	0.68	0.03	32.0 (6.8, 59.2)
gait speed	0.66	0.01	18.8 (−12.5, 49.9)

BMI, body mass index; BSA, body surface area; b.s.CI, bootstrap confidence interval

^*Comorbidities including diabetes mellitus, congestive heart failure, and coronary artery disease.

^†p<0.05 consider significantly different between each model and the based model.