RVAideMemoire (version 0.9-7)

surv.multcomp: Pairwise comparisons for survival analysis

Description

Perform pairwise comparisons between groups for equality of time to event. The function deals with coxph and survreg models.

Usage

surv.multcomp(formula, mat, data=NULL, strata = NULL, type = c("survreg", "coxph"), distribution = "exponential", p.method = "fdr")

Arguments

formula

a formula of the form a ~ b, where a is a Surv() object and b is a factor giving levels to be compared.

mat

matrix of comparisons (see help of the esticon() function in the package doBy).

data

an optional data frame containing the variables in the formula formula. By default the variables are taken from environment(formula).

strata

strata, if needed.

type

model type: "survreg" or "coxph".

distribution

distribution when a survreg model is used.

p.method

method for p-values correction. See help of the p.adjust() function.

Value

• model
  model formula.
• statistics
  test statistics.
• p.method
  method for p-values correction.
• p.value
  corrected p-values.
• comparisons
  data frame of results.

See Also

survreg, coxph

Examples

death<-c(sample(8:15,20,replace=TRUE),sample(12:20,20,replace=TRUE),sample(18:22,20,replace=TRUE))
groups<-factor(rep(LETTERS[1:3],each=20))
model1<-coxph(Surv(death)~groups)
model1
mat<-matrix(c(1,-1,0,0,1,-1,2,-1,-1),ncol=3,byrow=TRUE,dimnames=list(1:3,levels(groups)))
surv.multcomp(Surv(death)~groups,mat,type="coxph")

model2<-survreg(Surv(death)~groups,dist="weibull")
model2
surv.multcomp(Surv(death)~groups,mat,type="survreg",distribution="weibull")