Rat treatment data from Mantel et al
Rat treatment data from Mantel et al.
Three rats were chosen from each of 100 litters, one of which was
treated with a drug, and then all followed for tumor incidence.
litter:|| litter number from 1 to 100
rx:|| treatment,(1=drug, 0=control)
time:|| time to tumor or last follow-up
status:|| event status, 1=tumor and 0=censored
sex:|| male or female
Since only 2/150 of the male rats have a tumor, most analyses use
only females (odd numbered litters), e.g. Lee et al.
N. Mantel, N. R. Bohidar and J. L. Ciminera.
Mantel-Haenszel analyses of litter-matched time to response data,
with modifications for recovery of interlitter information.
Cancer Research, 37:3863-3868, 1977.
E. W. Lee, L. J. Wei, and D. Amato,
Cox-type regression analysis for large number of small groups of
correlated failure time observations,
in "Survival Analysis, State of the Art", Kluwer, 1992.
Dataset imported from https://www.r-project.org.