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Logrank test to compare survival curves adjusting for covariates

Usage

calogrank(ftime, fstatus, grp, cvt, strat=NULL)

Arguments

ftime

failure times

fstatus

status indicator

grp

group indicator

cvt

continuous covariates used for adjusted analysis

strat

stratification variable

Details

calogrank is the covariate adjusted version of k-sample survdiff. The function in its current form only does basic error checking.

References

Heller G. and Venkatraman E.S. (2004) A nonparametric test to compare survival distributions with covariate adjustment. JRSS-B 66, 719-733.

Examples

if (FALSE)   library(survival)
  data(pbc)
#> Warning: data set ‘pbc’ not found
  pbc1 <- pbc
#> Error: object 'pbc' not found
  pbc1$trt[pbc1$trt == -9] <- NA
#> Error: object 'pbc1' not found
  pbc1$copper[pbc1$copper == -9] <- NA
#> Error: object 'pbc1' not found
  # only death (2) is considered; transplant(1) is censored
  calogrank(pbc1$time, pbc1$status==2, pbc1$trt, pbc1[,c("copper")])
#> Loading required namespace: survival
#> Error: object 'pbc1' not found
  calogrank(pbc1$time, pbc1$status==2, pbc1$trt,
                                  pbc1[,c("protime", "copper")]) # \dontrun{}
#> Error: object 'pbc1' not found