MCPAN (version 1.1-21)

bronch: Rodent bronchial carcinoma data

Description

In a long term rodent carcinogenicity study on female B6C3F1 mice, the effect of vinylcyclohexene diepoxide on the incidence of murine alveolar/bronchiolar tumors was assessed. The mice were exposed to 0 mg/ml, (group 0), 25 mg/ml (group 1), 50 mg/ml (group 2), and 100 (group 3) mg/ml, with 50 animals per group.

Usage

data(bronch)

Format

A data frame with 200 observations on the following 3 variables.

group

a factor with levels 0, 1, 2, 3, labelling the control and the three dose groups

Y

a logical vector, indicating whether a tumour was present at time of death (if TRUE), or not (if FALSE)

time

a numeric vector, the time of death, counted in days? from begin of the study

Details

Not yet checked for consistency with the source!

References

Portier cJ and Bailer AJ (1989): Testing for increased carcinogenicity using survival-adjusted quantal response tests. Fundamental and Applied Toxicology 12, 731.

Examples

# NOT RUN {
data(bronch)
# raw tumour counts:

table(bronch[c("group","Y")])

# groupwise times of death:

boxplot(time ~ group, data=bronch, horizontal=TRUE)

# Using poly3estf, we can produce the
# summary statistics as presented in 
# Table 6.6, page 239, of Piegorsch and Bailer (1997):

poly3estf(status=bronch$Y, time=bronch$time, f=bronch$group)


# }