hr.comp.meta: Function to compare two concordance indices

Description Usage Arguments Details Value Author(s) References See Also Examples

Description

This function compares two lists of hazard ratios computed from the same survival data by using the function hazard.ratio. The statistical test is a Student t test for dependent samples.

Usage

1
hr.comp.meta(list.hr1, list.hr2, hetero = FALSE)

Arguments

list.hr1

first list of D indices as returned by the hazard.ratio function.

list.hr2

second list of D indices as returned by the hazard.ratio function.

hetero

if TRUE, a random effect model is use to compute the meta-estimators. Otherwise a fixed effect model is used.

Details

In meta-analysis, we estimate the statistic of interest in several independent datasets. It results a list of estimates such as list of hazard ratios. The two lists of hazrd ratios must be computed from the same samples (and corresponding survival data). The function computes a meta-estimator for the correlations between the two scores and uses a Student t test for dependent samples.

Value

p.value

p-value from the Student t test for the comparison hr1 > hr2.

hr1

meta-estimator of the first D index.

hr2

meta-estimator of the second D index.

Author(s)

Benjamin Haibe-Kains

References

Cochrane, W. G. (1954) "The combination of estimates from different experiments", Biometrics, 10, pages 101–129.

Haibe-Kains, B. and Desmedt, C. and Sotiriou, C. and Bontempi, G. (2008) "A comparative study of survival models for breast cancer prognostication based on microarray data: does a single gene beat them all?", Bioinformatics, 24, 19, pages 2200–2208.

See Also

concordance.index.

Examples

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
#first dataset
set.seed(12345)
age <- rnorm(100, 50, 10)
size <- rexp(100,1)
stime <- rexp(100)
cens <- runif(100,.5,2)
sevent <- as.numeric(stime <= cens)
stime <- pmin(stime, cens)
h1.1 <- hazard.ratio(x=age, surv.time=stime, surv.event=sevent)
h2.1 <- hazard.ratio(x=size, surv.time=stime, surv.event=sevent)
#second dataset
set.seed(54321)
age <- rnorm(110, 53, 10)
size <- rexp(110,1.1)
stime <- rexp(110)
cens <- runif(110,.55,2)
sevent <- as.numeric(stime <= cens)
stime <- pmin(stime, cens)
h1.2 <- hazard.ratio(x=age, surv.time=stime, surv.event=sevent)
h2.2 <- hazard.ratio(x=size, surv.time=stime, surv.event=sevent)
hr.comp.meta(list.hr1=list("hr.age1"=h1.1, "hr.age2"=h1.2),
  list.hr2=list("hr.size1"=h2.1, "hr.size2"=h2.2))

bhklab/survcomp documentation built on Dec. 26, 2021, 6:41 a.m.