vardiffC: Variance estimation of the difference between two correlated...

In compareC: Compare Two Correlated C Indices with Right-Censored Survival Outcome

Variance estimation of the difference between two correlated overall C indices

Description

This is a function used to estimate the variance of the difference between two correlated overall C indices

Usage

	vardiffC(timeX, statusX, scoreY, scoreZ)

Arguments

timeX	The vector of actual survival time X, one survival time for each observation
statusX	The matching vector of event indicator for time X, 1 if occured and 0 otherwise
scoreY	The vector of the first measured biomarker Y, one for each of the same observations, based on which the variance of the difference in overall C indices is to be estimated
scoreZ	The vector of the second measured biomarker Z, one for each of the same observations, based on which the variance of the difference in overall C indices is to be estimated

Value

est.vardiff_c	The estimated variance of the difference of two C indices
est.varCxy	The estimated variance of the C index for scoreY
est.varCxz	The estimated variance of the C index for scoreZ
est.cov	The estimated covariance between the two C indices for scoreY and that for scoreZ

Author(s)

Le Kang, Weijie Chen

References

Harrell FE, Califf RM, Pryor DB, Lee KL, and Rosati RA. (1982) Evaluating the yield of medical tests. The Journal of the American Medical Association, 247(18), 2543–2546

Pencina MJ and D'Agostino RB. (2004) Overall C as a measure of discrimination in survival analysis: model specific population value and confidence interval estimation. Statistics in Medicine, 23(13), 2109–2123

Kang L, Chen W, Petrick NA, and Gallas BD. (2014) Comparing two correlated C indices with right-censored survival outcome: a one-shot nonparametric approach. Statistics in Medicine, 34(4), 685–703, doi: 10.1002/sim.6370

See Also

estC,compareC

Examples

demo(testC)

compareC documentation built on April 26, 2022, 9:06 a.m.