Survival of Ventilating Tubes

Survival times of ventilating tubes of left and right ears in 78 children with otitis media.

data(ears)

Format

A data frame with 78 observations on the following 5 variables.

left

Survival time in month of tube in left ear.

lcens

Censoring indicator for left ear: 0 censored and 1 event.

right

Survival time in month of tube in right ear.

rcens

Censoring indicator for right ear: 0 censored and 1 event.

group

a factor with levels control and treat.

Source

Sin-Ho Jung and Jong-Hyeon Jeong (2003). Rank tests for clustered survival data. Lifetime Data Analysis, 9, 21-33.

References

V.M. Howie and R.H. Schwarz (1983). Acute otitis media: One year in general pediatric practice. American Journal of Diseases in Children, 137, 155-158.

D.W. Teele, J.O. Klein, B. Rosner et al. (1989). Epidemiology of otitis media during the first seven years of life in children in greater Boston. Journal of Infectious Diseases, 160, 89-94.

Examples

data(ears)
if (require(survival, quietly=TRUE)) {
  ls <- cscores(Surv(ears$left, ears$lcens), int=TRUE)
  perm.test(ls ~ group, data=ears)
}
#> 
#> 	2-sample Permutation Test
#> 
#> data:  ls by group
#> T = 748, p-value = 0.01222
#> alternative hypothesis: true mu is not equal to 0
#>