Performance of Restricted Mean Survival Time Based Methods and Traditional Survival Methods: An Application in an Oncological Data

Table 3

Multivariable analysis based on cox proportional hazard regression and restricted mean survival time based regression.

Parameter	Cox regression		Pseudovalue regression		IPCW regression (individual weights)
	HR (95% CI)		Difference in RSMT (95% CI)		Difference in RSMT (95% CI)
Age (continuous)	1.03(1.03,1.03)	<0.001	-3.89(-4.22,-3.55)	<0.001	-2.65(-3.18,-2.11)	<0.001
Sex, male	Time-varying		-24.85(-38.64,-11.06)	<0.001	-18.38(-46.87,10.11)	0.206
Year of diagnosis
1970s~1980s	1.41(1.25,1.59)	<0.001	-28.38(-2.68,-54.07)	0.03	-195.11(-224.25,-165.96)	<0.001
1990s~2000s	Reference		Reference		Reference
Race
White and black	Time-varying		-10.73(-26.64,5.19)	0.186	-27.61(-52.66,-2.55)	0.031
Other	Reference		Reference		Reference
Tumor size
>100 mm	Time-varying		-49.38(-84.87,-13.89)	0.006	-15.53(-30.21,-0.85)	0.038
Unknown	Time-varying		-11.82(-38.20,14.55)	0.38	-5.90(-20.14,8.35)	0.417
<100 mm	Reference		Reference		Reference
EOD
Metastasis	4.44(3.46,5.69)	<0.001	-202.21(-237.34,-167.08)	<0.001	-20.45(-43.36,2.46)	0.08
Local invasion	1.65(1.32,2.05)	<0.001	-89.90(-121.74,-58.06)	<0.001	1.68(-12.77,16.13)	0.82
Unknown	1.79(1.41,2.27)	<0.001	-113.04(-147.17,-78.91)	<0.001	38.85(23.92,53.78)	<0.001
Confined	Reference		Reference		Reference
AJCC staging
III + IV	Time-varying		-168.85(-196.05,-141.65)	<0.001	25.66(-4.16,55.47)	0.092
II	Time-varying		-61.40(-86.12,-36.68)	<0.001	19.42(-4.98,43.81)	0.119
Unknown	Time-varying		-88.88(-114.01,-63.75)	<0.001	73.84(54.56,93.12)	<0.001
I	Reference		Reference		Reference
Surgery, yes	0.58(0.53,0.64)	<0.001	36.22(19.23,53.21)	<0.001	53.01(17.35,88.67)	0.004
Radiation, yes	1.44(1.30,1.60)	<0.001	-45.76(-63.27,-28.25)	<0.001	-6.52(-58.84,45.80)	0.807
Chemotherapy, yes	Time-varying		-49.93(-67.87,-31.99)	<0.001	-58.58(-97.25,-19.91)	0.003

RMST, restricted mean survival time. IPCW, inverse probability of censored weighting. AJCC, American Joint Committee on Cancer for staging.