rats Rat treatment data from Mantel et al

Description

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.

Usage

rats
data(cancer, package="survival")

Format

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

Note

Since only 2/150 of the male rats have a tumor, most analyses use only females (odd numbered litters), e.g. Lee et al.

Source

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.

References

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.